The thermophysical properties of liquid Cr-Mn-Ni steel alloys (16 wt% Cr, 7 wt% Mn, and 3–9 wt% Ni) are investigated using the maximum bubble pressure method in which the manganese evaporation and change in chemical composition is very low after experimental trial. The surface tension of copper was measured as reference and experimental σ is in the range of literature values. It is shown that for AISI 304 austenitic steel the surface tension decreased by an increase of oxygen concentration in steel composition. For Cr-Ni and Cr-Mn-Ni steels, the temperature coefficient is positive which is explained by sulfur steel concentrations larger 50 mass ppm. A slight influence of nickel to the surface tension of Cr-Mn-Ni steels was experimentally observed where σ was lowered by rising weight percentage of nickel.