Australia's men's water polo team have lost their opening game of the FINA world championships 10-7 to Serbia.

The Aussie Sharks trailed the European superpower 4-3 at quarter-time and 6-3 at the long break before fighting their way back to 6-5 midway through the third term.

Serbia surged to victory by scoring four of the last six goals.

Australia's Billy Miller admitted it wasn't an ideal start to the tournament, but said it wasn't the end of their hopes.

"It wasn't the start we were looking for but there are plenty of positives to take from the game," Miller said.

"There were a few key areas in extra man defence that let us down and some poor decisions in attack but all in all it's the first game of the two week tournament and we will better for it in the next game."

Australia next take on Asian rivals China on Wednesday evening (AEST).