Grayson Gets Poison Chalice
Grayson beat off competition from John Ward of Cheltenham Town, Colin Calderwood of Nottingham Forest and Swansea City's Roberto Martinez for the award.
Blackpool were the form side in League One in April, registering maximum points from each of their five league games.
The month began with a narrow home win over Tranmere Rovers and also included impressive away wins at Huddersfield and Cheltenham.
Grayson's men rounded off April in style with a comprehensive win over League 1 champions Scunthorpe to leave them in with a chance of claiming an automatic promotion place on the final day of the season.
Chris Kamara, chairman of the Coca-Cola Manager of the Month Awards panel, said: 'Simon Grayson's side have enjoyed a wonderful run over the past few weeks, winning five games on the bounce to take them to within reach of stealing an automatic promotion place.
'Even if they do miss out on a top two spot Blackpool are the form side in League One at the moment and are a team that everyone will be fearing in the play-offs.'