Scottish Gas Networks was called to an area near Stockiemuir Road, in Bearsden, East Dunbartonshire, at around 3pm yesterday.
A large proportion of Stockiemuir Road was fenced off, causing delays for motorists.
The gas main was disturbed by workmen who were carrying out construction work.
Gas engineers were called out to what is understood to be the new Mugdock House Care Home to fix the problem after the alarm was raised. The home is due to open next year.
A spokeswoman for Scotland Gas Networks said: "The situation has been made safe and the gas leak has been isolated."