Healthcare professionals undergo frequent job stress due to exposure to high cognitive demands. The present research was carried out at the "Héroes del Moncada'' polyclinic in the municipality of Cárdenas, Matanzas. The objective is to apply indicators associated to mental fatigue. The indicators applied are: Simple Reaction Time and Yoshitake Test. Statgraphic Centurion 15.0 software is used as a tool for information processing. The results of the research obtained in this study show significant differences between before and after in some of the indicators applied, which evidences the presence of mental workload at the end of the working day. When applying the Yoshitake Test after finishing the assigned activity, all the health personnel of the study sample manifested the presence of subjective sensation of fatigue, highlighting both physical and mental fatigue.