The Australian Sex Party, which is running 29 candidates in Victoria alone, says churches should pay tax and the sale of marijuana should be regulated.

Party president and Victorian Senate candidate Fiona Patten says churches are the biggest land owners in the country yet they pay no tax, costing taxpayers about $20 billion a year.

"The biggest tax dodgers are the church," Ms Patten said at the party's campaign launch in Melbourne on Thursday.

"They should be paying their fair share of tax."

The party also wants marijuana to be regulated and taxed, compulsory sex and relationship education in schools and the legalisation of voluntary euthanasia.

The party is running candidates in every state and territory.

In the seat of Melbourne, the Australian Sex Party will preference Labor over the Greens, who are in a battle with Labor to retain the seat.

Ms Patten says her party has averaged about seven per cent of the vote in the last elections run in Victoria.

"I would hope that we would be sitting around that figure again and with any luck we will be picking up that Senate seat over Family First."

The launch included a new ad campaign and the release of "political condoms".