Here is Full Power Super Saiyan Gohan in his Chinese clothes he wore in the episode A Girl Named Lime and Several other episodes.

It is called the Mandarin Collar Dual-Frog Duangua, or Mandarin Collar Jacket or by it's popular name the Kung Fu outfit because of all the chinese kung fu movies this one appeared in and Mandarin black pants with Xiaoyuankou Buxie or Chinese cloth shoes/slippers.

The dual-frog duangua has always been my favorite amongst the Chinese wear specifically the white long sleeve and black pants ones mostly because of all the chinese martial arts movies I've watch and played the fighting game which characters wear them.

I want to one day get the white dragon style Mandarin Collar Jacket, black pants, and cloth shoes to complete.

In this pic Gohans pants at the ankles are opened legged while in the anime they are elastic ankle. I just love those the most.

I really don't know about the history of these fine Chinese clothings but here is where you can take alook at it [link]

Known Wearers:

Teen Gohan

Bruce Lee(Enter the Dragon and all other of his movies)

Forest and Marshall Law(Tekken games, costumes)

Stephen Chow (Kung Fu Hustle)

Donnie Yen (Ip Man)

Li Lianjie/Jet Li (FearLess)

Jackie Chan (Saw a pic)

I love Chinese every bit as I do Japanese.

In my opinion Gohan is Chinese just look at his life-style and the dragonball universe is not necessarily set in any specific place but they do have some basis of Chinese Culture which many of it had set a background for Gohan and his family. Even the Gi's aren't fully Japanese if you compare the clothing to both Japanese and Chinese.

P.S. I personally think Gohan is the best loooking Anime Character to wear it