Background: Mental illness is a growing public health issue affecting both patients and their family members. Family members play an important role in the recovery process but often experience stress and emotional burden. Nurses in inpatient psychiatric care have a key role in promoting family participation.

Aim: The aim of the study was to describe nurses' experiences of relatives' participation in psychiatric inpatient care.

Method: A structured mixed-method literature review was conducted. Systematic searches were performed in CINAHL, PsycInfo, and PubMed. Fifteen peer-reviewed qualitative and quantitative studies published between 2015 and 2025 were included following quality appraisal. Data were analysed using thematic analysis.

Results: Two main themes emerged: Family participation as an opportunity and Challenges to family participation. Family members were viewed as a valuable resource that supports patient recovery, enhances patient safety, and reduces stress for both patients and healthcare staff. However, confidentiality, patient autonomy, limited time and resources, and varying nurse attitudes and competence were identified as barriers to family participation.

Conclusion: Nurses generally have positive attitudes toward family participation, but practical and organisational barriers limit its implementation. The findings highlight the need for enhanced education, clear guidelines, and organisational support to strengthen family-focused care in inpatient psychiatric settings.