Abstract: The effects of heat on pollen grains was studied in pepper (Capsicum annuum L.) under greenhouse conditions using a completely randomized design. Seeds of the California Wander variety were grown in a growth chamber and flowers plucked and placed in 38�C (treatment) and 25�C (check) for a period of 8 h and consequently pollen viability, pollen tube growth and the growth of pollen tube inside the style was studied. Results indicate that pollen viability and pollen tube growth was considerably reduced at 38�C as compared with the check. In addition, pollen tube growth inside the style at 38�C was twisted and they grew in spiral and helical forms.