Putellas is the third winner of the prize, following in the footsteps of Ada Hegerberg, who won the inaugural women's Ballon d'Or in 2018, and United States World Cup star Megan Rapinoe, winner in 2019.
The 2020 Ballon d'Or awards were cancelled because of the pandemic.
Putellas captained Barcelona to victory in this year's Champions League, scoring a penalty in the final as her side hammered Chelsea 4-0 in Gothenburg.
She also won a Spanish league and cup double with Barça, the club she joined as a teenager in 2012, and helped her country qualify for the upcoming Women's Euro in England.
Her Barcelona and Spain teammate Jennifer Hermoso finished second in the voting, with Sam Kerr of Chelsea and Australia coming in third.
It completes an awards double for Putellas, who in August was named player of the year by European football's governing body UEFA.