Background: Mechanical reasoning (MR) is the ability to identify the components of a system and understand how they interact in order for the system to work. Different mechanical systems, such as those of wheels and gears, require different types of reasoning. Objective: This study seeks to analyze the relationship that working memory (WM) and processing speed (PS) have with MR. Method: One hundred seventy-three (173) university students were assessed through the DAT test which consisted of 30 MR problems, the symbol search subtest of the WAIS-III battery for assessing the PS, and the BIMET-V and BIMET-VE batteries to evaluate the WM verbal and visuospatial components. Results: Regression analyses showed that the proposed variables do not predict the performance in gear problems, while the visuospatial WM and the PS predict the performance in wheel problems. Discussion: The results sugge...