With the popularization of online autonomous learning and the development of artificial intelligence, more and more students are starting to use ChatGPT to assist learning. Research gaps exist in understanding the intersection of artificial intelligence (AI), ChatGPT, and education. Based on reviewing relevant literature from domestic and foreign scholars, the authors combine quantitative and qualitative research methods to explore the relationship between the usage of ChatGPT and the learning efficacy of Chinese college students. A total of 113 questionnaires were collected, and 100 valid questionnaires were obtained through screening eventually. The empirical results show that: looking up information, doing coursework and assisting with dissertation writing were common functions for college students to use ChatGPT; The impact of ChatGPT on the learning efficacy of domestic college students was relatively positive, but it was not yet significant; The frequency of using ChatGPT among college students of different genders showed significant differences, and the frequency of using ChatGPT among college students of different grades showed significant differences. Through interviews with 3 out of 100 students, the following conclusion was drawn: they generally believed that ChatGPT was more useful in solving difficult problems and could help them achieve success.