WSO may refer to:
Organizations World Safety Organization, an international professional association in safety World Sikh Organization, a Sikh religious and nonprofit organization
Music Waltham Symphony Orchestra, United States Wheeling Symphony Orchestra, United States Wichita Symphony Orchestra, United States Winnipeg Symphony Orchestra, Canada
Sports Cincinnati Open, a tennis tournament formerly called the "Western & Southern Open" Washington State Open, a USTA tennis tournament held in Seattle, Washington
Other uses WSO, a malicious web shell Washabo Airstrip, Suriname (IATA code: WSO) Weapon systems officer, an air officer in charge of armaments White superficial onychomycosis, a fungal infection of the nail plate
See also WS (disambiguation) WSOS (disambiguation)