Background Diabetic neuropathy, a serious microvascular consequence of diabetes mellitus (DM), affects up to 50% of those with type 1 and type 2 DM. It is the most typical DM complication. A person with diabetes is stated to have diabetic peripheral neuropathy once all other potential causes of peripheral nerve damage have been ruled out. This study's objective was to measure the serum sialic acid concentration in patients with type 2 DM and to assess if it could be used as an early marker of diabetic neuropathy Methods: This was a cross sectional study that was carried out on 40 patients subdivided into 3 groups, first group involved 25 patients with diabetic neuropathy, second group involved 15 patients without diabetic neuropathy and the third group involved 10 patients serving as control group. All patients were selected from those attending the outpatient diabetic clinic at Benha University Hospital between July 2017 and July 2018. Results: when comparing diabetic neuropathypatients to the control group of individuals, it was discovered that the serum sialic level was higher in diabetic patients with neuropathy than in diabetic patients without neuropathy. The age of diabetes diagnosis or the duration of diabetes were not related to serum sialic acid levels. Conclusions: serum sialic acid level is significantly increased in patients with diabetic neuropathy, and it is positively correlated with the glycemic control parameters.