Shell UK’s Braefoot Bay terminal was cordoned off following a gas leak in the early hours of Friday morning.
Emergency services spent several hours at the plant near Dalgety Bay.
A release of propane gas was discovered and the alarm raised at around 3am.
The marine terminal is part of the Shell Fife Natural Gas Liquids (NGL) Plant, which includes its site at Mossmorran, near Cowdenbeath.
Natural gas liquids from the North Sea are separated at Mossmorran, and propane, butane and gasoline are piped to Braefoot Bay for loading onto ships for export.
The road to the terminal was closed as police and firefighters attended the incident.
It was more than seven hours before they were stood down.
Fire service incident commander Station Manager Lynne Gow said: “The Scottish Fire and Rescue Service was alerted at 2.57am on Friday, May 17 to reports of a gas leak at a power plant in Fife.
“Operations control mobilised three fire engines to the Braefoot Bay plant, Aberdour, where crews worked to assist their emergency service colleagues.
“Firefighters thereafter left the scene.”
A police spokesperson said: “Police in Fife supported a multi-agency response to a propane gas release at Braefoot Bay, which was detected at 3am and resolved around 10.20am today.
“Cordons were put in place locally as a precautionary measure during this time, and officers have now left the area.”
A Shell spokesperson said normal operation had resumed following the incident.
She said: “We can confirm there was a propane gas leak at Braefoot Bay marine terminal in Fife today, May 17, 2019.
“The leak was detected by site personnel during routine operations at 3am this morning, and the situation was safely resolved by 10.20am.
“The emergency services were alerted and cordons were put in place as a precaution.
“Operations are now running as usual.”