The Office of the Worker Adviser (OWA) is an independent agency of the Ontario Ministry of Labour. The OWA provides free services to non-unionized injured workers and their survivors in workplace insurance matters (formerly called workers' compensation).

The OWA was established in 1985, along with the Office of the Employer Adviser (OEA) and the Workplace Safety and Insurance Appeals Tribunal (WSIAT).

The OWA is not part of the Workplace Safety and Insurance Board (WSIB).