Upper House members voted 21 to 19 in favour of the Democratic Labor Party bill.
The bill will now go to the Lower House for a vote.
DLP Member for Western Victoria Peter Kavanagh initiated the bill before presenting the Upper House with a petition carrying 2543 signatures from Western Victorians against fluoridation without referendums.
Mr Kavanagh said his party joined with Liberal, Nationaland Greens MPs to push the bill through the Upper House. He said it was the first DLP bill to pass through either house of parliament.
Mr Kavanagh was “surprised” but happy with the result.
“It all depended on the Liberal party but the (Labor members) were not at all happy about it,” he said.
“The ALP was quite upset and very insulting – they officially described the evidence on fluoridation as voodoo.”
Mr Kavanagh said State Government had rejected studies showing fluoridation was harmful and ineffective against tooth decay.
He doubted the Labor-dominated Lower House would pass the bill.
“However, it’s likely to put a good deal of pressure (on the government) and will modify the government’s position.”
Mr Kavanagh hoped Wednesday night’s vote would initiate further investigation of fluoridation.
The bill called for State Government to obtain permission through community referendums before fluoridating water supplies.
The Government has previously rejected calls for a referendum.