this research summarizes and compares the differences in forest fire regimes in the provinces of ontario, canada, and heilongjiang, china, as it relates to fire suppression techniques, human activities, and climate change. before 2007, the total burned area in heilongjiang was much larger compared than ontario. from 2000 to 2013, the total forest fire occurrences in ontario were greater than heilongjiang. compared to ontario, heilongjiang experienced more forest fires >100 ha in size. the main causes of forest fires in heilongjiang and ontario are human activities and lightning, respectively. most tree species in heilongjiang and ontario are fire resistant. but forest fires are major driver of forest ecology and forest stand dynamics in both heilongjiang and ontario. the fire weather index system used in ontario can also be applied in heilongjiang. historically, heilongjiang had relatively higher fine fuel moisture code and temperature compared to ontario. further, the rolling topography in heilongjiang causes the forest fire spread easier compared to ontario. climate change projections for this century suggest that forest fire regimes will become severe. we will experience more frequent fires, and more extreme weather events. in addition to climate change, human activities and the development of fire suppression technology can hold the key to the changes in fire regimes.