Abstract: A microorganism genetically modified for the bioproduction of 1,3-propanediol from sucrose, wherein the microorganism includes: a two-step metabolic pathway for the production of 1,3-propanediol, including a first step of decarboxylation of 4-hydroxy-2-ketobutyrate with an enzyme having a 2-keto acid decarboxylase activity, and a second step of reduction of the obtained 3-hydroxypropionaldehyde with an enzyme having hydroxy aldehyde reductase activity, and genes enabling the microorganism to utilize sucrose as sole carbon source. A method for the biological preparation of 1,3-propanediol by fermentation, including cultivating said microorganism genetically modified, wherein the culture is performed in an appropriate medium including a source of sucrose, and recovering the 1,3-propanediol being produced.