The conversion of paddy fields seriously impacts rice availability for national food reserves, so the government is implementing a sub-optimal land extension program. Indonesia has suboptimal land that has the potential to become a national rice barn if appropriately managed. The types of suboptimal land most widely used in rice cultivation are lowland and tidal swamps, where the community can work. This research analyzes the determinants of rice farmers' decisions in managing suboptimal land. This research was conducted in West Tanjung Jabung Regency, Jambi Province, with a sample of 90 rice farmers. Data were analyzed using the multinomial logistic regression method. The determining factors are seen from the demographic and economic aspects. The research results show that factors that significantly influence farmers' decisions to choose tidal land from the demographic aspect are age and farming experience; from the economic element are the number of family dependents, land ownership status, and non-farming income. The significant determining factors in farmers' decisions to manage lowland swamp land from the demographic aspect are age and farming experience, and from the economic element are the number of family dependents and non-farming income. From the research, recommendations that can maximize the use of suboptimal land are increasing promotion and education to the community about rice cultivation on suboptimal land, providing easy access for farmers to rent land, and it is hoped that farmers will continue to have non-farming income to balance household needs and procurement of capital and farming input.