BackgroundSleep disturbance is highly prevalent among post‐operative cardiac patients, with negative impacts on surgical recovery and rehabilitation. Post‐operative pain and anxiety commonly seen in cardiac surgery patients are associated with poor sleep. Sleep medications commonly used are not ideal with prolonged usage, and non‐pharmacological interventions can be good alternatives or complements.AimTo examine effectiveness of non‐pharmacological interventions in post‐operative cardiac settings on sleep quality, pain intensity and anxiety.DesignSystematic review and meta‐analysis.MethodsPubMed, CENTRAL, Embase, CINAHL, Scopus, CNKI and ProQuest Dissertations and Theses were searched on 12 October 2022. Randomised controlled trials of non‐pharmacological interventions examining sleep quality for adult post‐operative cardiac patients were included. Included studies were appraised using Cochrane Risk of Bias tool version 1. Meta‐analysis was conducted using RevMan version 5.4.1, and heterogeneity was assessed using I2 statistics and Cochran Q's test.ResultsEighteen studies involving 1701 participants were identified. Coronary artery bypass graft was most common. Non‐pharmacological interventions varied in types and duration. All intervention groups were compared to usual care, placebo, no interventions or active comparators. Statistically significant improvement in sleep quality (SMD = −.91, 95% CI = −1.17 to −.65) was found among intervention groups that explored cognitive behavioural therapy, relaxation techniques, exercise, massage, acupressure, aromatherapy, music, eye mask and earplugs. Pain intensity was reduced (SMD = −.63, 95% CI = −1.05 to −.20) with cognitive behavioural therapy, relaxation techniques, massage, music and eye mask. Anxiety was improved (SMD = −.21, 95% CI = −.38 to −.04) with exercise and music.ConclusionThe overall use of non‐pharmacological interventions can optimise sleep after cardiac surgery. Further research with greater methodological rigour is needed to investigate different intervention‐related characteristics while considering potential confounders.Relevance to Clinical PracticePost‐operative cardiac settings can consider incorporating non‐pharmacological interventions. Patients and healthcare providers can be better informed about the use of such interventions to improve sleep.RegistrationPROSPERO CRD42022384991.