Between the end of August and the middle and late September. According to official website of the State Education Bureau, universities in different regions start at different times, usually from the end of August to the middle and late September. Freshmen generally start school earlier than other grades because they need to participate in military training and other activities. Some schools may start school ahead of schedule, and the start time may change due to special reasons such as the weather. Therefore, the specific start time is subject to the official notice of the school.