This study aims to develop a valid and reliable test for assessing 5-6 year olds’ geometry and spatial perception skills. The sample consisted of 500 children who were chosen by using a purposive sampling technique. The content, criterion, face and construct validity were examined according to sensitivity, consistency and stability. Item difficulty value was from .16 to .81, separability changed from .29 to .64 and total item correlations changed from .26 to .56. The criterion validity was .94, KR-20 .84 and test retest reliability value was .80 “Geometry and Spatial Perception Test” has a valid and reliable structure and can be used to assess children’s geometric skills