Social desirability is a multicomponent personality trait referring to the tendency of individuals to regulate their answers to establish a positive impression, avoid criticism, or satisfy a need for social approval (Johnson & Fendrich, 2002; Paulhus, 1984). This study investigated the role played by the socially desirable response style assessed with the Marlowe-Crowne Social Desirability Scale (Crowne & Marlowe, 1960) on self-rated measures of affect (i.e., Center of Epidemiological Studies of Depression Scale; Radloff, 1977), metacognitive efficiency (i.e., Sensitivity to Memory Questionnaire; Cornoldi & De Beni, 2003; and Cognitive Failures Questionnaire; Borella, Carretti, Cornoldi, & DeBeni, 2007), and self-perceived psychological wellness (Psychological Wellness and Aging Questionnaire; De Beni, Borella, Carretti, Marigo, & Nava, 2007) in a sample composed of young (M = 24.6 years), old (M = 69.4 years), and very old (M = 81.9 years) adults counterbalanced by gender and education (i.e., ≤ 8 years versus > 8 years). Results revealed that social desirability alone predicted measures of affect and emotional competencies and contributed to predicting personal satisfaction, general perceived wellness, and self-rated cognitive efficiency. Overall, the present outcomes suggest clinical psychologists should pay attention to the crucial interference of social desirability in assessing wellness even in late adulthood, that is, in a developmental phase thought to be mainly characterized by reduced control of physical and psychological functions.