Both dramas are really similar in the way how they has a special class of "drop outs" dreaming to become something. Both dramas also have very similar feeling in them and similar friendship and slight romance mixed in.
Shimura Teppei (Fujigaya Taisuke) grew up watching his policeman father who would ride side-by-side in marathons because he was a motorcycle cop, and dreamt of being a marathon runner as a child. But Teppei’s father lost his job and disappeared. Teppei ruined himself by becoming a well-known delinquent in the area. Under the influence of his childhood friend, Yuichi, Teppei chose to become a policeman after graduating from high school. He miraculouslypassed the recruitment exam and entered the police academy. However, he has been assigned to a “class of reserves” (Goriki Ayame, Koyanagi Yu, Okamoto Azusa, Mizusawa Erina, Ishii Tomoya, Mori Ren) which is a gathering of odds and ends. There are eight of them and each day they are only instructed by the assistant teacher, Ryuzaki Misaki, to sweep the academy grounds.
A japanese drama with a different vibe but same setting! Without trying to spoil too much of the plot, similar to police university it has its own balance of funny moments and dramatic moments! I would say the main difference is that it has alot more characters and focues on some issues outside the main character (but are still relavent to the main characters development). For example a female police officer dealing with her feelings about the prejiduces she experienced as a women in the police force. There is also another character that deals with turning a new leaf (was a yankee before) after getting his friend involved in a crime he commited in the past. All in all, lots of intresting sub plots and exploration into why these characters chose to be police officers and wanted to go to school for it! Would recommend if you need more police dramas to watch after Police Universoty is done!