Recent studies of climate trends indicate that the annual mean temperature has increased by of 0.9°C over southern Canada (south of 60°North) since the beginning of the century. The largest warming occurred in the western region, mostly during winter and spring. During the same period, fewer days with extreme low temperatures were observed during the winter, however, no trends in extreme hot days were identified in the summer. Precipitation analyses have shown that the annual totals have increased by 12% in southern Canada. This increase was mainly due to an increase in small to moderate events, and no consistent trends were found in extreme precipitation over the same time. This study continues the analysis of climate trends and variability in Canada, but from a different perspective. Indices of climate change have been selected to determine whether the frequency and severity of some climate extremes have changes over the century. For examples, trends are computed in the number of frost-free days, length of growing season, days with snow, greatest multi-days precipitation. These indices are based on homogenized daily temperature and precipitation which are datasets adjusted for site relocation and changes in instruments. The analysis examines the temporal and spatial characteristics of selected climate change indices over two periods: 1950-2001 and 1900-2001.