Background: Very preterm (VPT) children and adolescents show executive, behavioural and socio-emotional difficulties that persist into adulthood. Despite the promising role of mindfulness-based intervention (MBI) in improving theses competences in children and adolescents, the effectiveness of an MBI has not been assessed in a VPT population so far. Aims: To describe the protocol and to evaluate the feasibility and acceptability of a clinical trial on an 8-week MBI program to enhance executive and socio-emotional competences in a cohort of VPT young adolescents. Study design: A randomised controlled trial (RCT) and a pre-post intervention designs. Participants: 164 VPT young adolescents from 10 to 14 years old, born before 32 gestational weeks, without major intellectual, sensory or physical impairments, and attending mainstream school, were invited to participate in an 8-week MBI program. Outcome measures: Completion rate of the study was recorded. Acceptability, satisfaction and attendance measures of the MBI were collected using self-reported questionnaires and registration of attendance. Results: Of the 63 participants who were enrolled in the study (38.2% of families invited to participate), 52 (82.5%) completed all assessments. Acceptability was high as shown by the high attendance rate in the sessions and the feedback evaluation questionnaire. Conclusions: Our findings suggest that an MBI is feasible to implement and show a high acceptability among participants. The use of an RCT design in our study constitutes the gold standard for testing the efficacy of such intervention in VPT young adolescents. If effective, the MBI program could potentially be a valuable tool for improving executive and socio-emotional competences in the vulnerable VPT population. Trial registration: ClinicalTrials, NCT04638101. Registered 19 November 2020 - retrospectively registered, http s://clinicaltrials.gov/show/NCT04638101.