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Stable, transgenic, sweetpotato plants have been developed using an improved somatic embryogenesis consisting of l) stage I—explants incubated in darkness for 14 days on MS medium with 2,4D (2.5 mg·liter–1) and 6-BAP (0.25 mg·liter–1) and 2) stage II—culture in light for 14 to 28 days on MS medium with ABA (2.5 mg·liter–1). Petiole or leaf explants of the genotype PI318846-3 were co-cultivated with Agrobacterium tumefaciens EHA 101 containing gusA::nptII fusion gene. Transgenic somatic embryos were selected on a kanamycin medium (100 mg·liter–1). The PCR analysis of the transgenic sweetpotato plants showed the presence of foreign genes in the sweetpotato genome. About 100 transgenic plants are being maintained under laboratory and greenhouse conditions. All the transgenic plants showed a strong expression of gusA gene in the histochemical GUS assay but showed quantitative differences in the chemiluminescent assay. The CaMV35S promoter shows a differential expression because there was some degree of tissue- and organ-specificity in the gusA expression. All transgenic plants appear normal with no phenotypic aberrations and are being tested for productivity traits.