The €320 million deal is subject to regulatory approval, a statement said.
Several months ago ProSiebenSat1 announced it would sell some of its units to reduce debt.
"Free television is our core activity. That is why the sale of C More fits our strategy," boss Patrick Tillieux said in a statement.
C More was part of the package acquired as part of the purchase of SBS. TV4 belongs to the family-owned Bonnier Group.
The move means that TV4 will acquire Canal Plus, which owns the broadcasting rights to a wide range of films and sporting events and is strongly placed on the market.
Canal Plus owns the rights to the English Premier League, Italy's Serie A, the NHL ice hockey league as well as Sweden's top football and ice hockey leagues.
The company also has broadcasting agreements with the vast majority of American and Nordic film companies.
"We are now establishing ourselves for the first time within the premium pay TV sector, a market that hes been developing broad distribution and strong growth for a number of years," said TV4 CEO Jan Scherman in a statement.
Scherman believes the acquisition of C More Entertainment will reduce TV4's reliance on advertising revenue.