Objective: The current study aimed to examine whether specific features of psychomotor retardation (PMR) and cognitive functioning established different profiles in unipolar (UD) and bipolar depression (BD). Methods: Two groups of age-matched patients with UD (n=54) and BD (n=20) completed the Montgomery-Asberg Depression Rating Scale (MADRS/60), the Montreal Cognitive Assessment (MoCA/30), and the Salpêtrière Retardation Rating Scale (SRRS/60). We analyzed the group effect and then performed intra-group analyses. Results: The BD patients have higher SRRS score, and lower MoCA score than UD despite no difference on the level of depression between UD and BD. Our results show that PMR can be predicted by the level of depression in UD and by the cognitive alteration and onset of disease in BD. Conclusion: PMR is a relevant marker of depression. Our results highlight the importance of concomitant evaluation of psychomotor and cognitive functions in the distinction of UD and BD symptoms.