The ruling relates to challenges to laws against brothels, living off the avails and soliciting.
Ontario's Appeal Court had previously struck down the laws against bawdy houses and altered the ban on living off the avails of prostitution to preclude exploitation.
It also upheld the ban on street prostitution.
The federal government appealed the decision that invalidated or altered the laws, while a group of sex-trade workers who brought the case initially appealed the soliciting ban.
The rulings were put on hold pending the outcome of the Supreme Court of Canada appeal.
The Supreme Court heard oral arguments in June.
At issue is whether the laws violate the rights of sex workers and whether they can then be justified as a reasonable infringement.