Yakushiji Ryouko no Kaiki Jikenbo

Both animes are about a special forces within the MPD that deals with supernatural cases only. 

Both offer the allusive, powerful jukujo. If you like powerful and mature women in anime you'll love these two. 

Another low-budget detective series.  

In fact I wonder how I cannot notice the similarity from th very beginning?! Firstly, they both involve police and detective job, and their tasks are really far from ordinary ones. Secondly, the characters are very alike. Male characters are both in some kind of surbodance to their partners, they are both hulk types. Women are bold, even risky depending on their partners a lot, though the latter might not notice that. Thus, if you like the pairing, police atmosphere and unusual cases watch both. 

Settings and plot in both anime have nothing in common, but for mystery element. However, the characters are really similar. Horo and Ryoko are powerful in their worlds, they both achieve the aims they have once set. Izumida and Lorence are their humble servants towards whom both heroines feel attraction. Both anime are slow in pace but it does not make them boring! 

both are about solving mysteries and bringing down organization. detective conan is more based on deductions and facts and yakushiji is more supernatural. they both have some romance in it and are full with suspense and some comical moments. highy recommend seeing both of these animes, they re story are different so theres no feelings of repetition but if you like watching one you will like the other  

In these animes, the lead guy is often being force by the lead girl to follow her in her adventures. The lead girls have a very lively and mischievous personality, while the guys have a more passive and introvert personality. Both animes deal with some kind of supernatural phenomena, and the main characters try to solve those. 

Both have a strong and beautiful female lead and a male assistant. Both have comedy, action, and supernatural themes.  

Both anime is about strong, clever and experienced women, felt in love with common japanese employee.  

Dark gothic animation about two female detectives who have some sort of socialization problem but also have an attitude of some kind. 

Both written by Toshiki Tanaka, Yakushiji Ryoko no Kaiko Jikenbo and Ginga Eiyuu Densetsu share a lot of similarities as far are characters and stories are concerned. The themes are pretty much alike too, and even if the settings are very different (space opera and modern-day Tokyo...), we can still feel the distinctive Tanaka touch in each of them, and the scripts are developped on the same pattern. If you liked one, you'll probably like the other. 

Not only both anime deal with some form of supernatural cases, they also share the same overall "mood" and even artstyle. Ryouko's Case File is set in the modern times while Nijuu Mensou is set in the fifties. If you like the pulp detective genre, you'll definitely find Ryouko's Case File and Nijuu Mesou no Musume refreshing. Although I must say that Ryouko's cases are reminiscent of X-Files... 

cinderella boy has much of the same atmosphere as ryoko's case files. the anime's about a poor man and rich ojoo-san running a detective agency together. there's interesting cases, about the same amount of action, but otherwise the main story is different enough that you won't find it a repetition of any other detective series. 

Both of these series hunt down the supernatural and make it so that it doesn't bother other people. 

Both feature female protaganasts who try to solve mysteries that seem supernatural but really are not. Or are they? 

Both stories deal with the tracking down of the supernatural and dealing with them so they won't effect other people. 

I will not go as far as to say Ryoko's Case file was on the same level as GITS, but it definitely had the same "Japanese politics" feeling when you watch it. On top of that, both are action-packed conspiracy series, with Case file tending more towards supernatural and pulp SF whereas GITS is pure hardcore cyberpunk SF (that even inspired the Wachowski Brothers into making the Matrix)