Diabetes UK has warned half of people with the condition are not meeting their blood pressure target.
Just 50.7% of people with diabetes met this target during 2009/10, according to analysis, which has barely improved since the previous year when 50% of people met the target.
This is despite the fact that high blood pressure increases the risk of diabetes-related complications such as heart disease, kidney failure and stroke.
The figures imply that more than 1.4 million of the 2.9 million people with diabetes have high blood pressure.
Diabetes UK said most people with diabetes (91%) are getting an annual blood pressure check, however, once people with high blood pressure have been identified, not enough is being done to help them bring it under control.
Barbara Young, chief executive of Diabetes UK, said, "Given the link between blood pressure and diabetes-related complications such as stroke, kidney failure and heart disease, it is extremely worrying that half of people with diabetes have high blood pressure.
"People with diabetes need to be aware that high blood pressure can have a hugely damaging effect on their health.
"But instead, we are in danger of high blood pressure becoming the norm in people with the condition, and this is one of the reasons they are experiencing record rates of stroke and kidney failure and are dying years younger than the rest of the population."
For someone without diabetes blood pressure should be no higher than 140/85 but with diabetes (or after a heart attack, stroke or coronary heart disease) blood pressure should be no higher than 130/80.
