Background: Strongyloides stercoralis, a soil transmitted helminth, is well known as a potentially fatal parasite in immunosuppressed patients. Objectives: The current study aimed to evaluate the prevalence of strongyloidiasis in diabetic patients, in the central parts of Mazandaran province, Iran, using coprological examination and enzyme-linked immunosorbent assay (ELISA). Methods: Fresh stool and serum samples were obtained from diabetic patients. The stool samples were examined using direct smear and formalin-ether concentration methods. The serum samples were tested for the existence of Strongyloides sp. antibodies using a commercial diagnostic kit (Strongyloides -ELISA). Results: The overall prevalence rates were 13.3% (4/30) and 25.6% (46/180) using parasitological and ELISA methods, respectively. The sensitivity and specificity of ELISA compared with stool examination were 100% and 84.6%, respectively. The seroprevalence rate of this infection was higher in females (27.3%) than males (19.5%), and among participants living in rural regions (31%) compared with urban areas (20%). The prevalence rate of Strongyloides sp. infection was higher in patients with diabetic foot (39.1%) compared with cases with non-diabetic foot (23.6%). It also was higher in insulin dependent patients (29.9%) compared with non-insulin dependent subjects (23%). However, these differences were not statistically significant which may have resulted from the small sample size. Conclusions: Our findings demonstrated a high seroprevalence of Strongyloides sp. infection in diabetic patients. Furthermore, this is the first seroprevalence study of strongyloidiasis in diabetic patients from Iran. It seems that the ELISA technique can be used for the diagnosis of individual cases and is a good screening assay to rule out strongyloidiasis in diabetic patients.