The Commerce Department said sales dropped 11.3 percent, the biggest decline since January, to a 355,000 unit annual rate, from a downwardly revised 400,000 units in October.
Analysts polled by Reuters had expected new home sales to increase to a 440,000 annual pace from October's previously reported 430,000 units.
The data is a setback for the housing market which has been showing strong signs of stabilizing after a three-year slump. A Realtors survey on Tuesday showed sales of previously owned home surged to their highest level in nearly three years last month, while the decline in prices was starting to fade.
Housing was the main trigger of the worst U.S. recession since the 1930s.
Still there were some positive signs in the November new home sales report. The median sale price for a new home rose 3.8 percent from October to $217,400, the highest level since May. Compared to a year-ago, the median sale price fell 1.9 percent.
The number of new homes on the market last month still fell to 235,000 units, the lowest since April 1971.
November's sales pace left the supply of homes available for sale at 7.9 months' worth, from 7.2 months in October.
(Reporting by Lucia Mutikani; Editing by Andrea Ricci)