The 23-year-old was presented with the award by Douglas McCrea from sponsor, McCrea Financial Services, at a gala dinner in Glasgow tonight.
Supporters voted for Harley in an online vote at www.glasgowwarriors.org from a shortlist of six players who had received the highest number of votes throughout the season for the McCrea Financial Services Player of the Month awards.
The Scotland international, who has made 97 appearances for the Warriors, has featured in every RaboDirect PRO12 game this season.
Glasgow Warriors beat Munster 16-15 at Scotstoun on Friday night and will now contest the RaboDirect PRO12 Final for the first time, when they take on Leinster at the RDS in Dublin on Saturday 31 May (kick-off 6.15pm).
Jonny Gray, in his first season as a full professional was voted the Players' Player of the Season, after being named the RaboDirect PRO12 Young Player of the Year earlier this month.
Other winners on the night included, Finn Russell, who was named Young Player of the Season after making 13 appearances for the club and being included in the Scotland squad for the first time for the upcoming games against USA and Canada.
Tommy Seymour's fantastic solo effort against Treviso in Italy last month was named Try of the Season. The touchdown completed Seymour's hat-trick that night and ensured a bonus-point win for the Warriors.
The Most Improved Player award was handed out to Gordon Reid, who scored the winning try against Munster on Friday night and this week celebrated a call-up to the Scotland squad for the summer tour.
James Eddie won the Coaches Award for the second consecutive year for the effort he continues to invest in improving himself, his teammates and the club, while Peter Murchie won the Club Ambassador of the Season award for the work he's done in the community.
The Test Player of the Season award was given to Alex Dunbar, who featured in all five RBS 6 Nations matches for Scotland and scored two tries in the win over Italy in February.
Award Winners
Player of the Season - Rob Harley
Players' Player of the Season - Jonny Gray
Young Player of the Season - Finn Russell
Try of the Season - Tommy Seymour (v Treviso)
Most Improved Player of the Season - Gordon Reid
Coaches Award 2013/14 - Spirit of Glasgow Warriors - James Eddie
Club Ambassador of the Season - Peter Murchie
Test Player of the Season - Alex Dunbar
Guinness PRO12
Suite 208, Alexandra House,
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