The woman, aged in her 40s, fell at Bendigo Racecourse at around 9.45am when her horse suffered an injury and stumbled.
Philpot, who fell during the conduct of a jump-out, was attended to by paramedics on-course but was tragically unable to be saved.
As a registered stable employee, Mrs Philpot rode trackwork for her husband and other Bendigo-based trainers since moving to Victoria.
Philpot was a long-term Queensland jockey who counted the Cairns Amateurs Cup among her winning achievements on the racetrack.
She moved to Bendigo in 2014 with her husband, licensed trainer Gus Philpot, and their daughters Jessie and Montana, so that Jessie could participate in the RV Apprentice Jockey Training Program (AJTP) where she is now in Year 4 and on loan interstate.
"This is a tragic accident and our thoughts and condolences are with the track rider's family and friends on the loss of a loved and valued member of the racing community", Racing Victoria chief executive Giles Thompson said in a statement.
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'Her sad passing will be felt by many within the industry'.
WorkSafe, with the co-operation of the Bendigo Jockey Club, are now investigating.
Racing Victoria paid tribute to Philpot and offered assistance to her family and to the local racing community.
'If ever you needed a hand or a plate of chicken wings, you could rely on Donna.
Rhonda Hall wrote: 'We will always treasure those times training our horses and the great times we had when they won'.