We study the effect of mutual fund allocation on China's IPO market under the new registration system. The introduction of mutual fund bids significantly increases the IPO offer price, resulting in a low initial short-term return and suppressed IPO underpricing. Those newly listed stocks witness lower volatility in the following weeks due to preferential allocation to the mutual fund at the primary market. Further analysis suggests that large investors' net purchase strengthens IPO after-market return and volatility. Besides, the effect of mutual fund participation on IPOs is stronger in places where the COVID-19 outbreak. This new evidence suggests that mutual fund allocation plays a critical role in IPO price discovery and decreases investor lottery trading.