Ninety per cent of bowel cancer cases are treatable when detected early but Bowel Cancer Australia says colonoscopy waiting times could be costing lives.

There are fears many Australians will die from bowel cancer because of colonoscopy waiting times.

Bowel Cancer Australia is calling on the Australian government to urgently address the "looming" crisis, after new research showed more than half of patients who return a positive screening result don't have the diagnostic procedure within the recommended 30 days.

An Australian Institute of Health and Welfare report reveals 83 per cent of people who receive a positive result from the government screening program don't undergo a colonoscopy within the recommended time.

Bowel Cancer Australia CEO Julien Wiggins says governments must "adequately" fund colonoscopy services to reduce the delays and save lives.

"Ninety per cent of bowel cancer cases are treatable when detected early, but early detection requires people with a positive screen or symptoms suggestive of bowel cancer to be able to access the necessary follow up procedure within the recommended time frame," Mr Wiggins said on Monday.