Jonathan Joseph (London Irish), Matt Kvesic (Worcester Warriors) and Matthew Morgan (Ospreys) completed the six finalists.
Over 3,600 fans voted in the LV= Breakthrough Player Award over a six week period with May coming out as the clear winner.
Commenting at the presentation of the LV= Breakthrough Player trophy this afternoon, May said:
"I'm really pleased to have won the award especially as it's voted for by the supporters - I'm sure I owe a lot of Gloucester fans a huge vote of thanks!
"The LV= Cup has been hugely important to Gloucester Rugby in the past few seasons, as a number of our younger players, myself included, have received valuable first team experience in the competition and I'm sure will continue to do so."
LV= Head of Sponsorship, Claire Jeromson was delighted with the response to the award's debut year:
"The response to the LV= Breakthrough Player Award has been fantastic. Clubs and supporters have all really got behind the initiative, which aims to recognise the young and upcoming talent that we see featured so regularly in the LV= Cup.
"I would like to thank all the clubs involved for helping to encourage their fan base to support their short-listed players."
Visit www.lv.com/rugby for information on the LV= Cup and details on how to purchase tickets for the LV= Cup final this Sunday at Sixways Stadium.
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