Abstract <p>Background: The aging phenomenon is occurring at a faster rate in the developing countries compared to the developed countries. The most important issue in aging is promoting health, maintaining the independence of the elderly, and continuing to live an active life. Since reference values for hand grip strength vary across different populations and geographic regions, this study aimed to determine the reference values for hand grip strength and its influencing factors in the elderly of Amirkola. Methods: This cross-sectional study was a part of the second phase of the Amirkola Elderly Cohort and was conducted on 1375 elderly individuals aged 60 years and above willing to participate in the study. Muscle strength was measured using a dynamometer (Digital Hand Grip Dynamometer) in kilograms (kg). Other variables examined included demographic and anthropometric information, which were extracted using appropriate questionnaires and tools. Results: Based on the data, the median hand grip strength for women was 18 kg (range 11–26 kg), and for men was 32 kg (range 18–44 kg). Age and sex had the greatest impact on hand grip strength. A significant relationship was also observed between chronic disease, physical activity, bone mineral density, and fat-free mass with hand grip strength (<i>P</i> = 0.0001). Body Mass Index (BMI) and fat mass had a positive and significant effect in men. Educational level and marital status had a significant effect in both groups. Conclusion: The main factors affecting hand grip strength were age and sex. Other influential factors included chronic disease, physical activity, bone mineral density, and fat-free mass.</p>