Police are investigating after a Mackay bar was robbed by a man with a gun and an accomplice last night.

Just after 9pm, two men entered the gaming lounge of the Wood Street business.

One of the men walked to the middle of the room while the other approached the bar and handed a staff member a note and demanded cash.

The staff member complied after the man revealed a firearm in a bag he was carrying.

Both men then left through the Gregory Street entrance to a waiting dark-coloured sedan.

It was last seen travelling south on Gregory Street and then onto Gordon Street.

Anyone who may have seen the vehicle around that time is urged to contact police.