Media playback is not supported on this device
They stretched their season-long unbeaten run to 20 games run by seeing off local rivals Cyncoed FC Ladies 6-0.
Cardiff Met's reward is to enter the Womens European Champions League qualifying rounds in August, 2016.
Cyncoed Ladies, however, are battling against the threat of relegation from the top flight of Welsh Womens football.
Cardiff Metropolitan Ladies have won the Welsh Premier Womens League title for the third successive season.