Abstract: Aiming at the problem of present liquid surface tension coefficient measuring method having the disadvantages of expensive measuring equipment and low measuring precision, a new method for measuring liquid surface tension coefficient was proposed. This method could complete the measure with a unequal inner diameter U-tube by using the local force balance method combined with the Laplace’s equation, MATLAB image processing and LabVIEW virtual instrument system. Compared with the present liquid surface tension coefficient measuring method-pulling and separating method, the proposed method has the advantages of high measuring precision, requiring less sample and low cost, etc.