Benton Fire and Rescue Department said the accident happened just before 11 a.m.
The victims were later identified by police as 58-year-old Zhang Ping and 49-year-old Wang Shuhong, and both suffered head injuries.
“The body has been taken to Bentong Hospital in Pahang,” said Pahang Fire and Rescue Department chief Dr Wan Mohamad Zaidi Wan Isa.
Three of the 21 passengers and the driver are believed to be locals, while the remaining 18 are Chinese – seven women and 11 men.
Earlier, a 21-second video went viral on social media showing the crashed bus and several emergency personnel already at the scene.
Genting Malaysia said in a statement that the bus, owned by a third-party operator, was carrying 18 tourists from China’s Yunnan province and was descending from Genting Highlands.
“Our deepest condolences go to the family and friends of those who lost their lives and we pray for a speedy recovery for those injured,” the statement said.
“We will provide updates as more information becomes available.”
Genting Highlands is a popular entertainment and tourist destination with indoor and outdoor theme parks, casinos and shopping centres.
Bernama later reported that the 32-year-old bus driver did not have a licence and had received 27 summonses in the past for various traffic offences.
