A news release says the foot and leg bone were seen late Tuesday afternoon floating in the water along the shore of Vancouver's False Creek, a body of water that wraps around the downtown core.
Police so far have no theories about how or why the foot ended up in the water, and say the B.C. Coroners Service is also involved.
In the past four years, about a dozen feet encased in shoes have washed up on beaches near Vancouver, along the southern Georgia Strait and off Washington State.
Most of the remains are still unidentified, although investigators have identified at least two of the feet as belonging to men who had been reported missing.
In previous cases, police have said it appeared the feet separated from bodies naturally in the water and foul play wasn't suspected.