Medical crowdfunding is a rapidly growing healthcare practice whereby individuals leverage online platforms to assemble numerous small donations for health-related needs. In China, due to limited medical resources and disparities between urban and rural public healthcare systems, medical crowdfunding can play a complementary role in supporting the current publicly-funded medical insurance system. To date, few studies have investigated the determinants of successful medical crowdfunding projects in China. By collecting data from the Tencent GongYi platform, one of the largest government-authorized online crowdfunding platforms in China, this exploratory study adopts a sequential qualitative-quantitative mixed-methods approach to identify potential factors that influence medical crowdfunding practices. The findings suggest that health-related characteristics have the most significant influence on the success of medical crowdfunding in China. Specifically, projects that target non-major diseases and diseases with low mortality rates and/or high frequency are more likely to draw significant attention and succeed. The stages of disease diagnosis and treatment also have an impact. In addition, a number of demographic and social factors, such as age, location, place of residence of the fundraiser, and the social capital of the project initiator were found to be significantly related to project success. This study sheds light on local practices in medical crowdfunding in China and provides insights into the design and implementation of medical crowdfunding projects.