Del Piero, 38, was an overwhelming choice for the best player in the A-League after a vote taken by almost 100 members of the FMA.
It was a double celebration for Del Piero who also landed Syndey FC's player of year gong on the same night.
Returning from a ruptured ACL, Kerr 19, played a leading role throughout the season in helping Sydney win the women’s national league title, also scoring in the 3-1 grand final win over Melbourne Victiory.
It is the first time the FMA has presented an award for the leading player in the W-League. Others in the running were Tameka Butt (Brisbane Roar), Jessica Fishlock (Melbourne Victory) and Teresa Polias (Sydney FC).
Former Italy and Juventus superstar Del Piero beat a strong field that included Daniel McBreen and Michael McGlinchey (Central Coast Mariners), Marco Rojas (Melbourne Victory), Jeremy Brockie (Wellington Phoenix), Eugene Galekovic (Adelaide United) and Nikolai Topor-Stanley and Youssef Hersi (Western Sydney).
Del Piero, who will play on for another season with the Sky Blues, joins a wonderful list of previous winners.
Carlos Hernandez was the inaugural winner in 2010 followed by Matt McKay (2011) and Besart Berisha (2012).
He had a stellar season with Sydney, showing the class and skill that made him one of the most recognisable players in the world game.
Along the way, he broke Sydney’s all-time scoring record with 14 goals, many among them worthy of being included in goal-of-the-season discussions.
He also was instrumental in giving this season's A-League a turbo-charge when he joined the Sky Blues only six weeks before the season started.
FMA president Ray Gatt paid tribute to Del Piero and Kerr on their awards, which were presented at Sydney’s awards night at Doltone House on Tuesday night.
'On and off the field, Alessandro and Sam have been wonderful ambassadors for their club and the game in general,’’ Gatt said.
'Their performances during the season were of the highest order – professional, classy and skilful.
'They have been inspirational to the latest crop of young players and will no doubt influence the new generation. They are a credit to themselves, their club and the game."
Meanwhile, was feted by 750 guests Sydney's Doltone House on Tuesday night.
It was a fitting end to his first Sydney FC campaign that saw the superstar elevate the A-League to new heights across the board. He also captured the club's golden boot accolade after notching 14 goals.
Del Piero polled 132 votes to nudge out Rhyan Grant (119) while Terry Antonis (67), Vedran Janjetovic (63) and Yairo Yau (55) rounded out the top five.
While Del Piero rightfully grabbed the plaudits, Grant was also rewarded for a tremendous breakout season by claiming the Sydney FC A-League Players’ player of the year award.
The 22-year-old played 25 games, claiming two goals and two assists, showing his value to the Sydney FC team while playing as a right back, left back, central defender, right midfielder and central midfielder.
His deeds saw him finish a very close second to Del Piero in the main award but they did not go un-noticed by his team mates, who voted him the most valuable player of the 2012-2013 season.
Peter Triantis took out the Youth League players’ player of the year award for his performances in the youth team before his elevation to the A-League side where he made 14 appearances in the top grade, earning an A-League contract for his efforts.
Teresa Polias won back-to-back W-League awards after she took out the 2012/13 Sydney FC Women’s League players’ player of the year as the Sky Blues celebrated a grand final win over the Melbourne Victory.
The contribution of W-League coach Alen Stajcic was also recognised as he was named the recipient of the Sydney FC Chairman’s Award for 2012-2013 by Sydney FC Chairman Scott Barlow.