Polyamines, including putrescine (Put), spermidine (Spd) and spermine (Spm), are polycationic compounds of low molecular weight that are widely distributed in living organisms. They are implicated in a variety of plant processes, such as floral and fruit development. In addition, correlation between polyamines and flower gender or fertility is reported in some plant species. Since polyamines, especially Spd and Spm share a common precursor, S-adenosylmethionine (SAM), with ethylene, they demonstrated competitive effects on functions in fruit development and ripening in many plants. Exogenous polyamines have been employed to regulate floral and fruit development and ripening in a lot of plants. Besides, polyamines have shown their potential for postharvest fruit management. Therefore, in this review, we focused on the involvement of polyamines in floral and fruit development along with perspectives of polyamine research.