The move came amid fears of attacks on the religious minority in revenge for events in Buddhist-dominated Myanmar.
Thousands of supporters of a hardline Islamist group staged protests in the border town of Cox's Bazar after Friday prayers, calling on Myanmar to halt what they called the "genocide" of the Rohingya -- who are in the minority in Myanmar.
Most of the Rohingya refugees have fled to camps around the Bangladesh border city where there were already 300,000 Rohingya before the latest unrest erupted on August 25.
Cox's Bazar police chief Iqbal Hossain said 550 police have been deployed in the region, including at 145 Buddhist temples, to prevent ethnic violence.
More From This Section
He said police had stepped up security so local Buddhists, who have been established for centuries, "don't feel panicked".
"It's a preventive measure," he told AFP. "We've also set up check-posts across the district."
The reinforcements have come from the port city of Chittagong to watch temples, including the 300-year-old Kendriya Shima Bihar at Ramu, which hosts important Buddhist relics.
District authorities have also set up an inter-religious communal harmony committee since the Rohingya crisis started.
Jyotirmoy Barua, a top lawyer from the Buddhist community, told AFP that some 20 armed police were at a temple at Ramu in Cox's Bazar today.
Buddhist leaders in Bangladesh have protested the anti- Rohingya violence in Myanmar's Rakhine state and have urged Myanmar to resolve the crisis.
They said there have been some minor incidents targeting the Buddhist community.
Police in neighbouring Chittagong district have also stepped up security at dozens of Buddhist temples, a senior police official told local media.
Buddhists make up less than one percent of Bangladesh's 160 million people. They are well integrated in society but have faced past attacks.
In 2012, some 25,000 Muslims attacked Buddhist temples and businesses around Cox's Bazar after a Buddhist allegedly put an image defaming the Koran on Facebook.