A generalized drop length–height method is introduced here for the determination of contact angle in the drop-on-fiber systems. This method overcomes some of the difficulties encountered in the practice by applying the common maximum drop length–height method to determine the contact angle. Furthermore, with this new generalized method a large part of a drop profile can be used in the calculation, which reduces the statistical error of the determination and improves the reliability and accuracy of the obtained results. The method has been examined using both the theoretically simulated and the experimentally obtained drop profiles. The accuracy of the method has been estimated to be in order of 0.5–1° for the drop profiles of usual experimental quality, which can be obtained using common digital image processing hardware and software.