The Iran hostage crisis film took the 'Best Motion Picture (Drama)' prize in addition to Affleck being named 'Best Director'.
Affleck described the Golden Globe win as a career milestone in his acceptance speech and has since expressed his enthusiasm further on Twitter.
"To hear your name included among directors I've long admired is incredible. To win? Wow, thank you HFPA. #GoldenGlobes," he wrote.
Photo gallery - Golden Globes press room:
Affleck has collected several awards for directing Argo, including a Critics' Choice Award and an honour from the San Diego Film Critics Society.
Argo is now playing in the US and the UK. Watch a trailer below: