The paper presents a morphological and anatomical study of flower and inflorescence of Nepeta L. species in Romania. Original data regarding the inflorescence type and sexual distribution of flower in Nepeta are discussed. The flowers of Nepeta are hermaphrodite in N. cataria, N. nuda ssp. nuda is a gynomonoecious plant and N. parviflora and N. ucranica ssp. ucranica are gynoecious. Morphology of glandular and non-glandular trichomes in calyx, corolla and bracts are studied for the first time. Three identification keys based on morpho-anatomical characteristics and sexual distribution of flower were elaborated.