BACKGROUND: Mindfulness-based interventions (MBIs) are known for their beneficial effects on positive and negative psychological factors. When applied in an occupational context, MBIs might help workers to cope with stress, increase their professional outcomes and wellbeing. OBJECTIVE: In this two-groups pre-post experimental design we tested the effect of our MBI, called Integral Meditation (IM), among the employers of an Italian service company by measuring positive and negative aspects of psychological wellbeing related to mindfulness and workplace functioning through eight self-report questionnaires (CORE-OM, FFMQ, WEMWBS, MAIA, PSS, PANAS, STAI-X1, SCS). METHOD: Forty-two voluntary non-clinical employers of the company, randomly assigned to the experimental or the control group, were analyzed. The experimental group underwent our IM program, which consists of 12 weekly meditation classes given after the afternoon shift, while the control group did not receive any intervention. Data was analyzed via linear mixed models. RESULTS: Statistically significant results were obtained for FFMQ observing subscale (β= 0.49, p = 0.014), WEMWBS (β= 5.31, p = 0.02), PSS (β= -3.31, p = 0.03), the whole scale of SCS (β= 0.47, p = 0.01) and self-judgment (β= 0.68, p = 0.003) and isolation (β= -0.66, p = 0.01) SCS subscales. Statistically significant results were also found in four out of eight subscales of MAIA: emotional awareness (β= 1.26, p < 0.001), self-regulation (β= 1.28, p < 0.001), body listening (β= 1.08, p < 0.001) and trusting (β= 1.1, p < 0.001). CONCLUSION: Our intervention has demonstrated to bring beneficial effects in a mindfulness subdomain, in perceived stress, self-compassion, interoception and psychological wellbeing. Based on our results, we conclude that our intervention was effective in increasing the positive aspects of wellbeing and in reducing stress.