The bus was proceeding to Manihatti, when the tree got uprooted due to strong winds and fell on the bus, killing a man on the spot, police said.
The injured, including four women, were admitted to the Government hospital here.
More than 160 trees, both big and small, got uprooted and fell on a 80-KM Ooty-Gudalur stretch, due to heavy rains, accompanied by winds since last night, police said.
Similarly, 12 trees fell on the Ooty-Kothagiri road, affecting traffic.
Meanwhile, District Collector P Shankar has declared a holiday for schools in the district tomorrow in view of the rains, officials said.