Fernandez, the tournament’s third seed, recorded two aces and four double faults.
She also won only 54.3 per cent of her first serves in a match that lasted 87 minutes on centre court at the Victoria Park Tennis Centre.
The 22-year-old from Laval, Que., converted two of three break points but saved only three of eight.
It was Fernandez’s first semifinal appearance since reaching the final of the Rothesay International in Eastbourne, England, in June.
Shnaider will take on second-seeded Katie Boulter of Britain in Sunday’s final.
WATCH | Fernandez falls at Hong Kong Open in semifinals:
Defending champion Leylah Fernandez’s (Laval, Que.) will not get a crack at winning back-to-back Hong Kong Open titles as she was defeated Saturday 6-4, 6-2 by Diana Shnaider in semifinal action.
