"We have at this moment, no reason whatsoever to believe that the Olympic Games in Tokyo will not open on the 23rd of July in the Olympic stadium in Tokyo," Bach said in an interview with Japan's Kyodo News.
"This is why there is no plan B and this is why we are fully committed to make these Games safe and successful," he said.
His comment comes amid growing doubts over the holding of the Games in Tokyo.
The Japanese capital and 10 other prefectures have been under a state of emergency as Japan has failed to rein in a third wave of the coronavirus.
The government has also decided to suspend the entry of all non-resident foreign nationals, including athletes, until 7 February.
A Kyodo survey showed earlier this month that about 80 percent of those polled said the postponed Olympics and the Paralympics should be cancelled or rescheduled.
Bach hinted that the number of spectators could be reduced, saying the IOC has to be "flexible" and may need to make "sacrifices" to protect the lives of those involved.
"As I said, the priority is the safety. When it comes to safety, then there can be no taboo," he added.
Dick Pound, the longest-serving IOC member, also told Kyodo on Wednesday that the postponed Games could go ahead without spectators despite the pandemic.
"The question is, is this a 'must-have' or 'nice-to-have?' It's nice to have spectators. But it's not a must-have," said the 78-year-old Canadian, an IOC member since 1978, according to Kyodo.
"Nobody can guarantee (that the Olympics will go ahead as planned). But I think there's a very, very, good chance that they can, and that they will," he said.
Earlier this month, Pound told the BBC that he was not sure if the Tokyo Games would take place as planned.
"I can't be certain because the ongoing elephant in the room would be the surges in the virus," he told the BBC.
However, Pound told Kyodo on Wednesday that "I think the IOC and the organisers are committed to going ahead with the Games, if at all possible.
"And so they're not going to cancel unless there's a consensus among the government, health authorities and the IOC that it would be too dangerous."
The pandemic forced the IOC and Japan in March 2020 to delay the Olympics by one year to this summer. The Games are due to open in six months time.