A total of 2.25 million people in the UK are diagnosed with Type 2 diabetes, which is linked to unhealthy lifestyles and obesity, and another 500,000 are thought to be undiagnosed.
The latest research, being presented at Diabetes UK's Annual Professional Conference in Glasgow, examined the napping habits of 16,480 older people in China.
A large proportion of the group (68 per cent) took a nap at least once a week.
Even when other factors were taken into account that may influence the result, the study found napping was linked with an increased risk of developing diabetes.
Overall, people who napped at least once a week had a 26 per cent greater risk of developing Type 2 diabetes compared with those who never took a nap.
The experts, led by a team from the University of Birmingham, said several factors may be behind the link, including the fact that people who nap are also probably taking less exercise.
In addition, napping during the day may disrupt night-time sleep - people who sleep for just a few hours a night are known to have a greater chance of developing Type 2.
Waking up from a short sleep also activates hormones and mechanisms in the body that stop insulin working effectively, the researchers said.
One of the experts, Dr Shahrad Taheri, from the University of Birmingham, added: "Our research provides us with an additional insight on the risk factors behind Type 2 diabetes.
"As the number of people with Type 2 diabetes keeps increasing, it is crucial that we do everything we can to help prevent people from developing the condition."
Dr Iain Frame, director of research at Diabetes UK, said: "We know from previous studies that looked at the link between disturbed night sleep patterns and the risk of developing Type 2 diabetes that interrupted sleep at night could increase the risk of developing Type 2 diabetes.
"We already know that people who are overweight or obese, and therefore more at risk of developing Type 2 diabetes, can have problems sleeping.
"This new research could be another step towards explaining the possible link between disturbed sleep patterns and Type 2 diabetes.
"However, in terms of being major risk factors for developing Type 2 diabetes, disturbed sleep or napping are likely to remain less significant than already established risk factors such as being overweight, being over the age of 40 or having a history of diabetes in the family."