The Wilhelmy balance was used for in vitro testing of surface active properties of natural phosphatidylcholines (PCs) as possible basis for surfactant replacement therapy. Saturated PC, dipalmitoylphosphatidylcholine (DPPC) and phospholipon (PL) had similar parameters of surface activity: minimal values of equilibrium surface tension (EST) and the longest surface spreading time (SST). Unsaturated egg and soybean PCs also shared similar values of surface activity parameters (EST and SST). Correlation between fatty acid saturation of PCs and EST or SST allows to consider both these parameters as informative ones for surface tension evaluation in the search of components for artificial surfactant. Since parameters of DPPC and PL surface activity were equivalent in their performance. they may be potentially employed for testing instead of DPPC as a possible base for artificial surfactant.