A modified express method of contact angle measurement based on determining the diameter of a drop with a known volume has been elaborated. The method offers a number of advantages: it can be used in an express manner for in situ dynamic investigation and makes it possible to observe inhomogeneity and anisotropy of hydrophilicity. The method is convenient in comparative measurements and does not require any special equipment. Using the proposed method, the possibility of hydrophilic control of some materials (silicate glass, TiO2 (anataze) and polymetilmetacrylate (PMMA)) by UV (ultra violet) and chloroform vapor treatment has been studied. In particular, hydrophilicity of PMMA after UV irradiation was observed, and it is shown that changes in hydrophilicity are connected with the surface oxidation of PMMA. The observed phenomenon of hydrophilicity control can be used in various technologies, such as liquid coating, printing, spray quenching, nanolithography, pharmacology and others.