Onondaga is the name of some places in North America:

• Onondaga, Michigan
• Onondaga, New York
• Onondaga, Ontario
• Onondaga County, New York
• Onondaga Lake
• Onondaga Reservation, New York
• Onondaga Township, Michigan

Other meanings:

• Onandaga Cave State Park in Leasburg, Missouri
• Onondaga Native American Iroquois First Nations group
• Onondaga (geological formation), a geological formation, a layer of dense limestone that outcrops in New York and Ontario, Canada
• Onondaga Community College in New York
• Onondaga Hill Middle School in New York
• HMCS Onondaga (S73), a submarine in the Royal Canadian Navy
• USS Onondaga, three ships of the US Navy