Oscillating drop method with levitation technique under the microgravity conditions has advantage of thermophysical properties measurements high-temperature liquids. Thermophysical properties of high-temperature melts are indispensable for numerical simulations of materials processing. Accurate data are necessary to improve the process modeling, which leads to cost-effective production of high-quality products. From the requirements the levitation technique, which provides containerless conditions during the measurements, is progressed for accurate measurements of the thermophysical properties of high-temperature liquids. Therefore, we are planning thermophysical properties of high-temperature melts in ISS using the materials-science laboratory-electromagnetic levitator (MSL-EML). The measurements will be performed by the international collaboration team including our science team. Using the oscillating drop method we obtain the surface tension from the surface oscillation frequency and also the viscosity from the dumping time of the surface oscillations under the microgravity conditions. However, for precise measurements of the surface oscillation we must be care the measurement conditions both of atmosphere, such as oxygen partial pressure (Po2) and external forces. The surface oscillations are very sensitive to Po2, so we must set the measurement conditions in the oscillating drop method under the controlled Po2 conditions. Moreover, the external force conditions affect on the droplet shape and the surface oscillation dumping. Even in the microgravity conditions, we must apply weak electromagnetic forces (EMF) to keep the sample position in the coils, so we must control the electromagnetic force for minimization of its effect on the modification of droplet shape and the dumping time of surface oscillations. From the requirements of the condition tuning for precise measurements of the surface oscillations under the microgravity conditions, we have been performed the measurements of surface oscillation under controlled Po2 conditions with change of EMF under microgravity conditions by the parabolic air plane flight. From levitation experiments under microgravity with the variations of external force conditions, we discuss about that how does the dumping time modification by the oscillation mode conditions affect on the viscosity values from the Rayleigh’s relations. Base on the present result, we discuss about the improvement of the analysis of surface oscillations to obtain the surface tension and the viscosity for precisely measurements in ISS.