Shounen Onmyouji

Both shows features a bishounen with a supernatural servant/friend of sorts with a close relationship nearing shounen-ai (although this isn't the case). The main characters are both onmyoujis, and both shows have an arc-based/episodic setting where the characters help others or generally fight to protect themselves from monsters or the antagonists, while having character development present throughout the series. 

Both have ayakashi and the protaganists have ayakashi familiars. Other similar areas can also be found if you watch ^^ 

A young boy must succeed his famous grandfather. Both also have supernatural and fantasy themes. 

Both deal with exterminating demons or spirits. In both anime the protagonists have a demon follower (Nyanko - Natsume Yuujinchou / Mokkun - Shounen Onmyouji) which are very similar to each other. 

Both animes talk about "Onmyou-do", its art and practice. Tokyo Ravens has a modern approach but Shounen Onmyouji takes it back to its traditional roots. 

A young, cute, and very kind boy uses his strong powers to exorcise deamons who are evil. He wants to protect everybody and everything. The young boy faces many emenies and near-death expericences. Secrets.desires.Sins. Many many things good and bad happens in this thrilling,powerful,addicting anime. ~there is also a lot of humor~ 

Both shows tell the story of a young boy who has to grow up quickly in order to fulfill his destiny and protect the people he cares about. Both Oz (PH) and Masahiro (SO) have a lot of heart and courage, and both wish to be treated like adults. Each boy is protected by someone older than him. Both Gilbert (PH) and Guren/Mokkun (SO) have dark and difficult pasts but are able to rise above these things in order to protect the protagonist. In addition, Akira Ishida voices a role in both anime and, though their personalities are different, Break (PH) and Seimei (SO) both fill the role of mentor and guide who, in their own way, keep the protagonist moving forward and learning more about their abilities. The art styles are similiar, both shows feature the element of using special abilities to fight off spirits/chains and both are a mix of action, drama and humor. If you like one you will probably enjoy the other! read more 

Both anime are set in our own world, thou in diffrent times (Shounen Onmoyouji is set several houndreds years ago, Ghost Hunt is set in present day world) and they are about individuals exorcising evil spirits and protecting others from curses. It should be noted, that althought both anime have very similar main theme, Shounen is more action oriented and Ghost Hunt is more about puzzle solving. 

These animes have similar stories. They both fight demons/youkais with magic and they have Onmyoujis and shikigamis in common. Also, two of the main characters, Masahiro and Itsuki, both have a special ability with their eyes. 

Both of them use chants to kill the demons or at least render it powerless. They have very powerful animal spirits that help them get rid of the demons. They are both going to be successors to the head family shine... 

There are many similarities between Shounen Onmyouji, and Inuyasha. Masahiro is half spirit fox, and half mortal. Inuyasha is half dog demon, and half human. Masahiro's partner Mokkun is very much like Shipo. Then their is Princess Fujiwara no Akiko, who is very much like Kagome. Akiko can see demons and is attacked by them often. Kagome is the recarnation of a priestess who can defeat demons with holy arrows. The main reason for the same similarities is that both animes deal with hunting demons, becoming stronger, and protecting the spirit world and the real world. 

well its a shounen action type anime with awesome, very funny and unique characters it has a good storyline and awesome art and animation .If you liked Shounen Onmyouji youll probably like Fairy Tail 

Both main characters are little boys with big ambitions and a lot of heart. Both are always going out of their way to help others and care a lot about the people who support them. Both boys also have to learn, from square one, how to take care of themselves and fight monsters/spirits. Mokkun (SO) and Niche (TB) also share the Pet/Protector element. If you like Tegami Bachi Reverse, I think you'll love Shounen Onmyouji! 

Both about youkai and onmyouji. Main characters have something in similar too. Like both are grandsons of a great person that need to be surpassed. ( Nurarihyon in case of Rikuo and Abe no Seimei in case of Masahiro)  

Similar era and characters' costumes and Japanese ancient mythology themes. Both anime have supernatural beings and a main character with a power to see them. Shounen Onmyouji deals with ayakashi(aka familiar) and is action-packed, while Mushishi has a slower pace, 'mushi' and darker themes.  

Demon/god protects priest(ess). The demon gods both have different forms that they are in while fighting and day-to-day. In Shounen Onmyouji: Mokun(Guren) is "rescued" by Masahiro when Masahiro was a child because normally when children see him they cry. And of course we all know that when we make babies cry, you feel horrible. But Masahiro smiled at Guren. Then Guren(called Mo-Kun by Mashiro)vows to protect Masahiro at all costs. In Zenki: Zenki is the god protector of the world. But when his seal is broken and when Chiaki breaks his seal to save the world from peril, he isn't what he seems to be. He is rude, crude, and needs to have a second seal placed on him when he isn't battling because if he doesn't have that seal... He will try and kill Chiaki in order to be free.  read more 

Both are about The MC making friends with ayakashi, and growing into their power. 

both are centered around exorcists. in both main duo is a young human exorcist and their demon buddy with sealed powers (who switches forms between a cutie mascot and a hot piece of ass). both are set in era different from modern days. 

Monster helps human defeat monsters. Except that in Shounen Onmyouji the monster/shinigami actually likes the main character/onmyoji. Both main characters are relatives of great priests/monks/onmyouji/anything that has to do with a temple. These are so similar. When I was watching Ushio no Tora, the first thing I thought of was "Shounen Onmyouji"  

Both main characters are little boys with big ambitions and a lot of heart. Both are always going out of their way to help others and care a lot about the people around them. Mokkun (SO) and Niche (TB) also share the Pet/Protector element. If you like Tegami Bachi, I think you'll love Shounen Onmyouji! 

They both involve demons/duras and fight to protect the world from evil. Also the relationship between yuki and luka is similar to masahiro and touga, both of them have a very strong master/servant bond. The characters in both animes have supernatural powers as well. These two animes have a lot of similarities.  

both of supernatural aura, and both have a protagonist with a strong bond of a friend-brother bond with a familiar, if u liked Hakkendedn u wil love it  

Both are in the same era, also, in both there´s a war between demons and humans.  

There both are about a young Buddhist exorcists (SO 13 - AY - 16) who have got probs with it 

Shaman King also mentions about the Onmyouji practice especially the Asakura clan. Although Shaman King has only little scenes about Onmyōdō, they also talk about Shikigamis as a powerful Spirit for the Shaman. 

It has that master/servant relationship. An adult serving a child. 

Both have the magic and the bishonen. Both are slashable (although Yami no Matsuei has far greater potential in this area than Shounen Onmyouji). But most importantly, both the anime have heroes who command the Twelve Shikigami! Shikigami rock!! 

They have the same epic style and historical-mystical feel to it.  

The same historical setting + romance involved (In Uta Koi. more than in Shounen Onmyouji) 

The similarity between these two is the idea of purifying / exorcising evil. They are not really similar otherwise, they are more like paralel series, they are ahout exterminating evil in 2 different cultures. Shounen Onmyoujy deals with Asian beliefs (youkai, shikigami, etc), while Ao no Exorcist deals with more like European beliefs (satan, devils, familiars).  

Both animes talk about Onmyou-do and develop a plot out of it.