This study evaluated the nutritional quality of rural households in Iran in 2023 using household income-expenditure data and the nutritional performance matrix to identify dietary patterns. The Mean Adequacy Ratio (MAR) and one-sample t-test were used to assess food security across provinces. The results revealed that calcium intake was below the minimum requirement nationwide, while carbohydrate consumption among adults was two to three times higher than recommended. Iron intake was adequate in most provinces, except for North Khorasan, Tehran, Mazandaran, Gilan, West Azerbaijan, Semnan, and Golestan. Protein intake exceeded the required threshold in most provinces, except for Gilan, Hormozgan, and West Azerbaijan. In terms of vitamins, only residents of Markazi and Fars met the minimum requirement for vitamin A, while those in Markazi, Mazandaran, Chaharmahal and Bakhtiari, and Bushehr met the requirement for vitamin C. Other provinces showed varying degrees of deficiency. Based on calorie criteria, 22 out of 31 provinces were considered food secure. However, MAR results indicated that rural areas in all provinces remained food insecure. Chaharmahal and Bakhtiari, South Khorasan, Fars, Kurdistan, and Bushehr were closer to food security, while West Azerbaijan, Gilan, Golestan, Hormozgan, and Sistan and Baluchestan faced the greatest challenges. The one-sample t-test also revealed significant differences in provincial food security indices compared to the national average: 14 provinces were above, 14 below, and 3 showed no significant difference. These findings highlight the urgent need for region-specific policies to improve nutritional security in rural Iran.