The partner of a 20-year-old Kyabram woman who died in a jet-ski collision in Thailand will be charged over her death.

Thomas Keating, 22, had told police sunlight reflecting off the sea made it impossible for him to see the jet-ski being ridden by his girlfriend, Emily Jayne Collie.

Lifeguards tried to revive her on the beach but she was later pronounced dead at a local hospital.

Thai police say Mr Keating will be charged with reckless driving causing death.