The trade association, which represents all convenience retailers in Scotland, believes such a move would remove "conflict situations" from stores when young people are attempting to buy alcohol and would help retailers to comply with the new licensing laws.
SGF chief executive John Drummond said: "Incidents of threats, violence and racist abuse are all too common when some customers are challenged about their age. Often, the worst incidents occur when people of a legal age take offence at a request for ID from staff.
"Staff need and deserve the protection a comprehensive proof of age scheme will provide.
"It is time to bring balance to the legislative burden placed on retailers. Industry initiatives can only go so far - government leadership is crucial."
The SGF wants the government to ensure free cards are rolled out across the country by 2009, when Scotland's Licensing Act 2005 comes into force.
The call for the introduction of a proof of age card is part of the SGF's Retail Manifesto 2007 which sets out the demands of Scotland's 6,000 convenience retailers.