Roberts said, "I'm really chuffed to win this award and to be picked from all of the players in the Principality Premiership.
"I've really enjoyed my rugby this season, playing for Cardiff in this League has given me a chance to play regular rugby at a good standard while continuing with my studies. Despite some difficult conditions during the winter months, the majority of the games have been hugely competitive and of a high standard. It's certainly been a step-up for me from age grade rugby.
"As a team, we have come together well as a group and produced some good performances in the second half of the season.
"I hope I can go on from here and get some regional rugby under my belt before next season kicks in."
Jamie's coach at Cardiff and Blues academy manager, Justin Burnell believes the youngster has 'everything it takes.'
"Jamie has really hit form at the right time. He is big, physical, fast - he really has every attribute needed to make it in the professional game.
"Since coming back to fitness and form, Jamie has had a major influence on our good performances of late.
"I feel Jamie would bring something extra to the regional side so hopefully we will be seeing a lot more of him in the future."
Jamie will receive £100 in a Principality account from Premiership sponsors Principality Building Society.
Margaret Berridge, customer service consultant at the Queen Street branch of Principality Building Society in Cardiff said, "Heartfelt congratulations to Jamie on winning the Principality Player of the Month award. Jamie is a central figure in the Cardiff team who contributed to their solid wins against Ebbw Vale and Neath during March. I wish him well as we enter the last few weeks of the season.
"As the second season of the Principality Building Society Premiership draws to a close, it's an opportunity to reflect on a great period of rugby. I look forward to August and the kick-off to a brand new season and wish Cardiff every success."
Jamie Roberts factfile
DOB - 08/ 11/ 86
Place of Birth - Newport
Club - Cardiff
Position - Full Back
Player Most Admired - Percy Montgomery
Most Respected Sportsman - Eric Cantona
Nickname - Square head or lump head
Your Biggest Rugby influence (who or what) - Mike Rayer and Blues academy coaches
Other sports played - County cricket up to Under 15 level
Occupation - Rugby Player and medical student
Unusual facts - A keen guitarist and sat A level exams in Argentina during U21 World Cup