5240 Kwasan is a main-belt asteroid with an estimated diameter of about 20 km. It was discovered on December 7, 1990 by Suzuki and Urata at Toyota. The semi-major axis is 2.38 AU, the eccentricity is 0.101 and the inclination is 5.61 degrees.
This asteroid was observed on 2 nights nights during September 2015. The data was sufficient to derive a period of 5.909 hours.