This research aims at investigating the effect of Van Hiele model based learning to geometric concept understanding seen from spatial visualizing ability. This research used quasi experimental with the post test only control group design. The data was collected using test metodh. The data was collected using geometric concept understanding and spatial visualizing ability. The data were analyzed using Anacova one way. The research samples are 70 fifth grade students in cluster II of Buleleng subdistrict. The results of the research show that: (1) there is significant diference of geometric concept understanding between students following Van Hiele model based learning and those following conventional learning, (2) after co-variable of spatial visualizing ability controlled, there is significant diference of geometric concept understanding between students following Van Hiele model based learning and those following conventional learning, (3) spatial visualizing ability co-variable has contribution to student's geometric concept understanding. Based on those result, it is concluded that Van Hiele model based learning implementation has a significant effect on increasing the geometric understanding concept seen from spatial visualizing ability of fifth grade students in cluster II Buleleng subdistrict.