Xu Zhengxi (Chinese: 徐正溪, born 5 May 1985), also known as Jeremy Tsui, Izz Xu, Jones Xu or Jeremy Jones Xu is a Chinese actor. He gained increased popularity with his portrayal of Yuwen Hu in the historical drama The Legend of Dugu, as well as his role as an antagonist in the period drama Siege in Fog.

He speaks Mandarin, Cantonese and English. Before his success, he suffered from hyperthyroidism but recovered.