The invention provides a stirring-free method and a stirring-free device for producing sodium nitrate through continuous conversion. The device mainly comprises an ammoxidation-prepared oxynitride system, a soda ash solution preparing system and a sodium nitrite mother solution conversion system, wherein the sodium nitrite mother solution conversion system mainly comprises a converter tower, a pre-converter tower, an absorption tower, a motor solution storage tank and matched pumps and pipelines. Nitric acid and the mother solution undergo conversion reaction in the converter tower; conversion solution reflows and back washes the bottom of the converter tower; gas of the converter tower is separated by a gas-liquid separator and enters the pre-converter tower; and converted gas and oxygen-mixed air are mixed quantitatively and then the mixture enters the absorption tower for absorption to prepare feed solution. The method and the device have the advantages that: the production of the sodium nitrate can be continuously performed; the reflowing and backwashing of the conversion solution replaces air stirring; in the converted gas absorbing process, the converted gas is added with the oxygen-mixed air in a ratio, the process operation is optimized, and loads of the adsorption tower and subsequent processing procedure are lightened; the production capacity is improved; energy consumption is reduced; NOx emission is decreased; and the method and the device are favorable for environmental protection.