On August 20, 2015, Zheng Kai posted a number of photos with his girlfriend Cheng Xiaoyue on Weibo and admitted their relationship. Zheng Kai posted photos and expressed his deep feelings, saying that he hopes to travel to every corner of the world with his girlfriend.

Recently, Zheng Kai appeared at Shanghai Pudong Airport with his beautiful girlfriend Cheng Xiaoyue. Zheng Kai looked at his girlfriend lovingly and smiled very happily. When Zheng Kai interacted with fans, his girlfriend waited patiently on the side, and then took her to board the plane. This pair is rarely sweet.

Cheng Xiaoyue is a typical ABC (American Born Chinese) girl with a bold and unrestrained style. She often posts various sexy photos on the dating software Instagram. Her mother is a famous brand executive. Cheng Xiaoyue has frequent interactions and close relationships with many celebrities in the industry, including "boyfriend" Dou Xiao.

In January 2014, she and her mother attended the wedding of Yang Mi and Hawick Lau.

In May 2014, Cheng Xiaoyue also low-key attended the press conference of the movie "Wolf Totem" starring Dou Xiao during the Shanghai Film Festival.