Provided is a liquid-gas separator of a direct liquid feed fuel cell. The liquid-gas separator includes an empty ball shaped main body; a gas extraction membrane which is attached to an opening formed in the main body, and selectively extracts gas from the main body; an inlet which is formed in the main body and guides the liquid and gas into the main body; an outlet which is formed on the main body and guides the liquid to the outside of the main body; and a flexible tube having a hollow structure, one end of which is connected to the outlet and the other end of which is immersed in the liquid fuel.