About 15% of global agricultural lands are exposed to high salinity, resulting in low crop yields and reduced food supplies. Attempts to develop salinity tolerant crops via selection and breeding have not been sufficient. Bacterial mannitol-1-phophate Dehydrogenase (mtlD) has been known for its tolerance to salinity. Maize is the third cereal crop (after wheat and rice) that is severely affected by soil salinity. We have genetically engineered maize plants with the bacterial mtlD gene, confirmed the integration and expression of this transgene in upto forth progenies, and have confirmed that transgenic plants transcribing the mtlD gene have higher rate of photosynthesis and are more tolerant to different concentrations of NaCl (especially at 200 mM level) as compared with their wild-type nontransgenic control plants.