A school bus driver has been taken to Bega Hospital in a stable condition following an accident on Towamba Road, west of Eden, at about 8.30am Thursday.

A NSW Ambulance spokeswoman said the 25-seater school bus was on its side when paramedics arrived at the scene.

 About 20 students were on board but it does not appear any were seriously injured. 

"The male driver, aged about 40, suffered a medical incident and was transported to Bega Hospital in a stable condition," the spokeswoman said.

It is understood the bus was picking up students to take to Eden Marine High School at the time of the accident.

Eden Marine High School principal Ian Moorehead said the school had put its critical incident plan in place.

A NSW Department of Education spokeswoman said counselling was provided to the students and their parents at the school.

"While some students sustained some bumps and scrapes, none of the students was injured seriously and they were able to attend school after the accident occurred," the spokeswoman said.

"The principal praised the students for working together to contact emergency services and provide assistance and support to the bus driver and each other, while waiting for help to arrive," she said.

Sapphire Coast Buslines managing director Jamie Klemm said the driver suffered "no significant injuries".

Ms Klemm said the driver would undergo assessment to determine what happened before the accident.

The school bus run would continue as normal, she said.

A NSW Fire Service spokesman said the unit had been called to a milk tanker fire north of Genoa earlier this morning.

The unit had been back in Eden only several minutes when it was called to the Towamba roll-over.

At the scene, the officers helped the children out of the bus and then assisted the injured driver.

"It's been a very busy morning for us, there are only a handful of us," he said.