Many regions of Iran suffer of water deficit stress which affects survival, growth and yield of medicinal plants specially mint species. To evaluate the response of three Mentha species (peppermint ‗Mentha piperita‗, spearmint ‗Mentha spicata‗ and Wild mint ‗Mentha longifolia‗) to four levels of soil moisture regimes (100, 80, 60 and 40 of field capacity) a pot trail was arranged in a completely randomized design with five replications and carried out in 2010-2011 at College of Agriculture Ferdowsi university of Mashhad. In this experiment mint plants were harvested two times in a period of 7-8 months. The results showed that soil moisture regimes have significant effect on plant survival% (PS %), growth characteristics and total yield of dry matter of mint species at the both harvest. In the first and second cut PS% of wild mint and peppermint in 60% FC were decreased about 30% as compare as control treatment, but spearmint completely survived. Interaction effect of species and soil moisture regimes significantly affected number of total, lateral and tiller branches, number of leaves in mentioned branches and total yield of dry matter in both harvest. In the first harvest no. of total branches in spearmint did not impress by 60% FC, but decreased about 20% and 17% in wild mint and peppermint, respectively. While in the second harvest no. of total branches in spearmint at 60% of FC was 40% lower than control treatment and mentioned parameter in peppermint and wild mint were 73 and 93% lower than 100% of FC. The highest no. of leaves in 100% of FC in the first cut appertained to the lateral branches in all three species, but in the second cut no. of leaves in tillers in spearmint, wild mint and peppermint were 46, 48 and 100% more than lateral branches, respectively. Although in wild and peppermint the maximum yield of dry matter were obtained in 100 percent of FC in both harvest, but in spearmint the highest yield of dry matter in the first and second harvest were observed in 100 and 80% of FC, respectively. Results indicated that spearmint is more tolerant than peppermint and wildmint to water deficit stress during growing season.

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