Hello, yes, ETF funds are index funds. ETF funds follow a specific index and buy all or part of the stocks in the index. Commonly used indexes include SSE 50 Index and CSI 300 Index. Most of them take the constituent stocks in these indexes as investment targets, and form a portfolio as a whole, so ETFs belong to index funds. However, index funds include ETF funds, but index funds are not necessarily ETF funds. ETF funds can only be traded on exchanges, both index funds traded on exchanges and index funds not traded on exchanges.