Understanding the level of development and analyzing inequalities in various geographical areas and economic sectors is a tool for more appropriate and balanced planning and policymaking. In this regard, the aim of the present research was comparative analysis of the agricultural development in the COUNTIES of MAZANDARAN province, one of the most important areas for agricultural and livestock production in the country, using the Composite Index (CI) method. By systematically reviewing the literature and selecting 52 indicators across five dimensions of the agricultural system, animal husbandry, agricultural institutions and industries, crop farming, horticulture, and agricultural mechanization were identified and necessary data were obtained from valid statistical sources. The indicators were normalized using the method of division by the mean, and for selecting the weights of dimensions and indicators, the Analytic Network Process (ANP) technique was employed based on the opinions of agricultural experts in MAZANDARAN Province. The results of the CI showed that the COUNTIES of Amol, Sari, and Joybar obtained the highest development scores. Additionally, cluster analysis results indicated that only 14% of the COUNTIES in the province, including Amol, Joybar, and Sari, belonged to the developed category. Furthermore, 23% of the COUNTIES, including Babol, Babolsar, Behshahr, Qaemshahr, and Fereydunkenar were developed, relatively. The results also showed that about 27% COUNTIES including Ramsar, Mahmoudabad, Nur, Tonekabon, Abbasabad, and Kelardasht were less developed. It should also be mentioned that 36% of COUNTIES, including Chalus, Savadkooh, North Savadkooh, Simorgh, Galugah, Miandorud, Neka, and Nowshahr were categorized within undeveloped COUNTIES in terms of agricultural development composite index. In this study, to demonstrate the spatial analysis of the agricultural development status, a geographic information system was used. Based on the research data, it is necessary to pay attention to the agricultural development in COUNTIES with low development levels by policy-makers, planners, and implementers of agricultural development at the national and provincial levels.