Abstract: A new method for measuring coefficient of surface tension of liquid is designed by improving equipment of the experiment. New calculation formula is proposed based on force analysis of the metal ring. It corrects the used rough method which ignoring the weight of liquid. This new method has easy operation，and experiment data show that it has high accuracy and good stability. By a careful analysis of the new experimental results， some mistakes in related literatures are corrected.

Key words: pulled off method, surface tension coefficient, force analysis, sensitivity