The 23-year-old has racked up more than 860 million streams on the service, beating Eminem and Coldplay, who came second and third respectively.
His latest album, x, which hit the million sales mark in the UK this week, was played 430 million times.
Katy Perry was the year's most streamed female artist, with Ariana Grande second and Lana Del Rey third.
The Dark Horse singer took the top spot from Rihanna, who held the position for the previous two years,
Spotify said that more than 50 million users listened to 7 billion hours of music in the whole of 2014.
The service's most listened-to track was Happy by Pharrell Williams, which had more than 260 million plays.
British act Clean Bandit were in second position for their song Rather Be while DJ Calvin Harris' came third, with Summer.
Here are some of Spotify's most-streamed charts
Most-played artists
Most-played groups
Most-played songs
Male artist
Female artist
Most-played albums
Most-played artists (UK)
Most-played songs (UK)
Most-played albums (UK)