•We study the determinants of IPO underwriting market share in China.•Underwriting quality is overall positively related to underwriting market share.•Underwriter central government ownership is significantly related to market share.•Underwriting quality plays an increasingly important role in enhancing market share. This paper investigates the determinants of initial public offering (IPO) underwriting market share in China. Using a sample of underwriters in China’s IPO market during 2004–2012, we find the following results. First, underwriting quality is overall positively related to underwriting market share. Second, individual underwriting quality measures are significantly related to market share as well: Affiliated star analysts are valued by both state-owned enterprise (SOE) and non-SOE (NSOE) issuers. The post-IPO performance of previous clients (industry specialization) is a significant determinant of market share in the SOE (NSOE) IPO market. Third, central government ownership of underwriters is a significant determinant of market share in the SOE market. Finally, a further test on regulatory change shows that underwriting quality is playing an increasingly important role in enhancing underwriting market share in China’s new issue reform era.