Stoneworts are a conserved group within green algae which usually inhabit in submerged conditions of slow running and standing water. Charales is a difficult taxonomical group regarding species identification. This paper records 13 species of charophytes within three genera found in about eighty localities from Iran. The taxa Chara connivens, C. contraria, C. crassicaulis, C. fibrosa, C. grovesii, C. gymnophylla (two varieties C. gymnophylla var. gymnophylla and C. gymnophylla var. rohlenae), C. kirghisorum, C. pedunculata, C. socotrensioides, C. tomentosa, C. vulgaris (C. vulgaris var. longibracteata and C. vulgaris var. vulgaris), Nitella hyalina and Tolypella glomerata were studied, including vegetative and oospore characteristics of them. C. vulgaris and C. gymnophylla, are the most common species. The species C. kohrangiana is proposed as a new monoecious species characterized by stipulodes developed in one row, anterior and posterior bract-cells, ecorticate branchlets and diplostichous incomplete axial cortex. C. kohrangiana belongs to subgenus Charopsis section Agardhia subsection Agardhia.