Dramatic hot air balloon rescue at Melbourne's Port Phillip Bay

Nine passengers jumped from a hovering hot air balloon and onto a boat at Melbourne's Port Phillip Bay following fears the balloon was dangerously low on fuel.

It is believed the balloon missed its landing at Dendy Park in Brighton due its low fuel and was found hovering 500 metres offshore near Black Rock on Saturday morning.

Metropolitan Fire Brigade (MFB) and water police travelled to the scene at about 8:30am to find the balloon floating just 20m above the water and slowly losing altitude.

With the help of emergency services, the nine passengers climbed out of the basket, slid down a rope and onto the deck of a coast guard rescue boat below.

MFB spokesman Steve Moore said the balloon was reported to be about 500 metres from shore and 40 metres above the water.

"The basket of the balloon was positioned over the bow of the boat and initially three passengers were evacuated from the balloon to the boat," he told AAP.

"This reduced the load on the balloon and allowed it to fly higher for a while.

"The balloon again lost altitude, more passengers were evacuated and the balloon returned to a safer distance above the water."

The balloon gained altitude altitude and authorities shepherded it as the pilot guided it to Safety Beach on the Mornington Peninsula.

The passengers have been transported to Beaumaris Yacht Squadron where paramedics will assess them.

Meanwhile, another balloon made an scheduled landing in a park in the suburb of Aspendale.