The flowmeter based on Kerioly force principle may be used directly to measure mass flow.This eliminates the short comings of some tran-ditional methods. The flow meter has some unique features. It can be ap-lied to various fluids; it is in sensitive to impuritries causing no pressure loss and large conversion error and resulting in high availability. This simply structured flowrneter is suitable for use in havsh circumstance. In this paper workingprinciples of the flow meter are analysed.