The position was confirmed by the party’s leader at Westminster, Angus Robertson.
Mr Robertson said his party believed in fixed-term parliaments but would not stand in the way of an early election.
The next general election had been due to be held in 2020, but the Fixed Term Parliaments Act allows for one to be held earlier if two-thirds of MPs are in favour.
MPs are expected to approve Prime Minister Theresa May’s plan to hold an 8 June poll on Wednesday.
Labour and the Liberal Democrats have already said they support the move.