Potato buds cvs. ҅ Valor' and 'Spunta' were cultured in vitro on MS solid medium with 0.2 mg -1 BAP. The resulting plantlets were irradiated with gamma radiation doses 10, 20, 30, 40 and 50 Gy. Irradiated segments were transferred onto fresh MS with BAP and plantlets survival percentage was calculated after eight weeks. Gamma radiation caused the death of 3.8% to 81% in cv. ҅ Spunta' and 2.9% to 83.9% in cv. ҅ Valor'. Microtubers produced from irradiated plantlets were decreased with increasing gamma radiation doses, with notable changes in shape, size and numbers. The proline contents in irradiated plantlets were steady increase with gamma radiation doses. The genomic DNA of the two cultivars and ten radiation treatments was amplified with 10 RAPD primers that generated 53 polymorphic bands. The highest number of genetic identity was 0.9672 showed between irradiated plantlets with 20 and 30 Gy in cv. ҅ Valor'. However, the highest genetic distance was 0.3995 observed between irradiated plantlets with dose 20 Gy in cv. ҅ Valor' and 30 Gy in cv. ҅ Spunta'. The dendrogram generated by cluster analysis distinguished the irradiated plantlets genetically.