Board president Ann Hannah says stricter mortgage lending guidelines have prompted some buyers to move to the sidelines.
Home sales in the Greater Toronto Area totalled 5,793 for November, down from 6,908 a year ago.
The average selling price was up 1.6 per cent at $485,328, compared with $477,582 in November 2011.
The board says the moderate price growth compared with previous months was largely due to a different mix in detached home sales this year.
The share of detached homes over $1 million was down substantially, brought down the overall average price.
On Monday, Finance Minister Jim Flaherty said he was pleased housing was moderating in Canada, a shift in the mortgage market he attributed in part to his decision to tighten borrowing rules in July.
Flaherty made mortgage payments more expensive by dropping the maximum amortization period to 25 years.
Nationally, the housing slowdown was a big part of the disappointing economic downturn recorded in the third quarter, with the sector falling 3.5 per cent annualized.