This work was conducted to study the effect of fruit and seed characteristics on the quality of the guava (Psidium guajava L.) seed. It was studied as well different germination conditions which may affect the seed germination, dormancy and vigour. Fresh seeds were stored for 120 days, to verify also the seed viability curve. The data showed no differences in the germination when seeds from different fruits were used. For the vigour test, the best results were obtained when the seeds were extracted from the collected fruits, in relation to those gathered on the floor. In the experiment carried out to verify the influence of different temperatures on germination, it was observed a significant improvement when it was used 20-30°C (supported by the vigour test). The best substratum for germination was the filter paper treatment, when the seeds were placed on it. When the seeds were stored for six months, the best results were obtained using both filter paper or roll of paper towel. For the studies of light/darkness effects, the best germination results were found when the process occurred on light, both with fresh or stored seeds. When the guava seeds were stored under different conditions, the germination was mantained up to 30 days. Nevertheless, after 60 days, there was a decrease of at least 20 percentual points when the seeds were stored at 30°C in hermetic conditions; this was caused by the secundary dormancy that occurred under these conditions.