Polar vs Grizzly Bear - Who will fight better and win? A lot of people are curious to find out who would win in a fight between Polar Bear vs. Grizzly bear. It is important to note that polar bears are larger compared to grizzly bears and have more powerful paws and sharp teeth but grizzly bears are robust, more aggressive and have excellent bone structure as compared to the Polar bear. Polar bears are the biggest among their species but not as ferocious as the others. They have a longer and thinner skull as compared to the grizzly. The grizzly bear has a shorter, heavy and thick head and also possesses a powerful and robust shoulder structure. In icy circumstances, a Grizzly Bear will show more aggression against Polar, and many will agree that the grizzly bear will come out on top. When the ice melts, and the polar bear is in the surroundings of a grizzly bear, the grizzly bear has sufficient advantages to battle with the Polar bear, so grizzly is the winner. A fight between Grizzly bear vs Polar bear would indeed be very interesting to watch.