In this research, it was intended to determine the effects of geometrical-mechanical intelligence game activities on the spatial abilities of secondary school seventh grade students. The research was designed according to quasi-experimental design with pre-test and post-test control groups and conducted with two experimental and two control groups. The study group of this research included a total of 117 seventh grade students who took and did not take elective intelligence games course in a secondary school located in Turkey. In the study, experimental-I group played intelligence games activities with concrete materials, experimental-II played intelligence games on PC, control-I group played intelligence games that were recommended by the Ministry of National Education and control-II group did not play any of the intelligence games. Before, and after the empirical processes that lasted nine weeks, "Spatial Visualization Test", "Spatial Relations Test" and "Spatial Orientation Test" were used as data collection tools. Paired samples t-test and one-way analysis of variance for independent samples were used in data analysis. The results obtained from the research showed that the spatial visualization and spatial relations skills of students have significantly improved according to the activities recommended by the Ministry of National Education in both concrete materials and computer games.