"If current trends continue, the figure will rise from the 384,000 per year now to 506,000 in 2040," said the study. It means around one-third more people will be diagnosed with cancer every year in comparison to current levels.
The charity said the main reason behind the projection is the growing and aging population.
During the next two decades, new cancer patients in the UK are estimated to become older.
"Currently, around 5 in 10 new cancer cases were in people aged 70 and this figure could be 6 in 10 by 2040," it said.
"Today's analysis provides a stark reminder of the challenges the NHS (National Health Service) in England is set to face in years to come," said Cancer Research UK's chief executive Michelle Mitchell about the projection.
"Cancer patients are already facing unacceptably long waits for diagnosis and treatment, and staff in cancer services are working very hard," she added.
The charity said the "NHS risks being overwhelmed by the sheer volume of new cancer diagnoses" if the government will not take concrete action to handle the problem