In this study, the responses of pollen tubes to spermidine treatments (10 µM, 25 µM, 50 µM, 100 µM, 250 µM, or 500 µM) were investigated in Actinidia deliciosa, by focusing on pollen germination rate, pollen tube length, organizations of actin filaments, concentrations of Ca+2, pH, reactive oxygen species and distributions of callose and cellulose. According to findings, the only positive effect was detected after 10 µM spermidine treatment while the most negative acute effect was detected after 500 µM spermidine treatment and, further experiments were done in these groups. 10 µM spermidine increased the pollen tube length by changing the concentration of apex localized reactive oxygen species. 500 µM spermidine decreased the pollen tube length by changing the apex localized Ca+2, pH, and reactive oxygen species concentration. Findings would contribute to the understanding of the effects of polyamines on pollen tubes.