We present results of two-color VR photometry of the intermediate polar RXS J1803. The data were aquired using the Korean 1-m telescope located at Mt. Lemmon, USA. Different "high" and "low" luminosity states, similar to other intermediate polars, were discovered. No statistically significant variability of the color index with varying luminosity was detected. The orbital variability was found to be not statistically significant. Spin maxima timings were determined, as well as the photometric ephemeris for the time interval of our observations. The spin period variations, caused by interaction of the accretion structure with the rotating magnetic white dwarf, were also detected. These variations are of complicated character, and their study requires further observations. We determine the color transformation coefficients for our photometric systems, and improve on the secondary photometric standards.

• Ivan L. Andronov(Department of High and Applied Mathematics, Odessa National Maritime University)
• YongGi Kim(University Observatory, Chungbuk National University/Institute for Basic Science Research, Chungbuk National Unieversity/Department of Physics and Astronomy)
• Joh-Na Yoon(University Observatory, Chungbuk National University)
• Vitalii V. Breus(Department of High and Applied Mathematics, Odessa National Maritime University)
• Tammy A. Smecker-Hane(Department of Physics and Astronomy)
• Lidia L. Chinarova(Astronomical Observatory, Odessa National University)
• Wonyong Han(Korea Astronomy Observatory and Space Science Institute)