The prevalence of Internet addiction and influential factors associated with Internet addiction among freshmen college students were investigated in this study. A total of 3557 first-year university students from a university in northwest China were surveyed with Young's 20-item Internet Addiction Test (IAT) questionnaire, a Self-Rating Depression scale (SDS), a Self-Rating Anxiety scale (SAS), and a basic information questionnaire. A rate of 6.44% of the participants surveyed showed Internet addiction. The students with Internet addiction had higher scores of SDS and SAS compared with those without Internet addiction (p < 0.01). There were significant positive correlations between SDS and SAS scores and Internet addiction (p < 0.001). Multiple logistic regression analyses showed that a single-parent family, the age of first exposure to Internet use, the age of the student, city residence, and homesickness were significantly associated with Internet addiction (p < 0.01). Special and closer attention should be paid to these factors, and a risk-focus approach should be implemented in university freshmen with depression, anxiety, and other influential factors associated with Internet addiction at the beginning of their university life to guarantee the fulfillment of their academic study and graduation.