This research investigates the readiness of construction industry organisations to adopt primary prevention-based approaches to workplace mental health management. The construction sector's high-pressure environment contributes to poor mental health among workers, necessitating proactive strategies to mitigate job stressors. Despite the preference for primary prevention over reactive strategies, there is a lack of studies on organisational readiness for such changes in this industry. Considering the latest Occupational Health and Safety Amendment (Psychological Health) Regulations 2022 (Vic), which clarify employer duties to identify psychosocial hazards and implement preventative risk controls to protect worker psychological health. This study aims to fill this gap by assessing organisational readiness levels through a qualitative approach, involving document analysis, case studies, and semi-structured interviews. The analysis is guided by an organisational readiness framework encompassing structural and psychological dimensions. Findings indicate leadership commitment, integration with existing safety systems, and external regulatory and industry support emerging as key enablers. Persistent barriers include competing operational priorities, limited organisational capability, and residual stigma surrounding mental health. Findings will inform recommendations for effective implementation of prevention-based workplace mental health management, providing actionable insights for policymakers, regulators, and industry stakeholders. This study contributes to understanding how to bridge barriers and optimise resources for successful organisational change for better worker wellbeing and possibly suicide prevention that may be linked to poor mental health outcomes.