To know the speed performance of "ARAON" in Arctic ice field, the measurement of ice properties which is ice thickness & strength, snow depth and free board were performed on July 2010. The measuring method of nautical signals such as heading angle, power of engine, wind & current information etc. was described in this paper. The speed sea trials in ice were performed on the four different positions with different ice properties and engine powers because the uniform level ice is not detected in the Chukchi Sea. The test field was partially constrained ice floe with hummocks and it was superposed with small broken ice pieces each other. All of the measured ice properties were compared and evaluated according to the results of sea trial. The relations between speed, ice thickness, strength and power were summarized. Consequently according to the sea trial results, the speed of ARAON is 2.78knots at the 2.49m ice thickness with 6.55MW engine power.