We analyze the relationship between insider trading density and the future stock returns in Chinese listed companies. We introduce a new aspect of the trading pattern, insider trading density, to investigate the information advantage held by insiders. Insiders who trade at a low density during their tenure are less likely to be expected to trade than high trading density insiders. The expectedness of trading patterns reflects insiders’ trading incentives and conveys valuable information to predict future stock prices. Controlling for company, deal, and insider-specific characteristics, we find that low trading density insiders earn higher excess returns than high trading density insiders in a portfolio mimicking long strong purchases and short strong sales. In addition, we show that the insider’s position is a source of information advantage: prominent officers such as CEOs and CFOs are more likely to be low trading density insiders, while non-executive directors and supervisors are more likely to be high trading density insiders.