To provide theoretical bases for improving yield and quality of cultivation,regulating flower time and breeding efficiently,the morphological observation,paraffin section and semithin section were used to investigate the process and characteristics of the flower bud differentiation and anther development of French marigold (Tagetes patula L.) at both spring and autumn.The results showed that French mariglod had a typical capitulum consisted of ray florets and disk florets.The differentiation of flower bud was not beginning until the first two pairs of leaf primordium differentiation.The differentiation process of inflorescence was consistent with the sequence as follows:inflorescence primordium differentiation phase,bract primordium differentiation phase,ray floret primordium differentiation phase,disk floret primordium differentiation phase,ray floret differentistion phase and disk floret differentistion phase.There were differences in the initial and duration time of the differentiation of flower bud in different species and at different seasons,showing earlier time at autumn.The process of anther development was as follows:archesporial cell,sporogenous cell,microspore mother cell,dyad,tetrad,microspore,and matured pollen grain.The tapetum is amoeboid tapetum and the matured pollen grain is tri-cellular pollen.