The initial reports indicated that coffee is a short day plant. Data later reported, however, revealed that coffee may flower under long day photoperiod. The present study was carried out in order to evaluate the effect of day length on plants of Mundo Novo, Catuaí Amarelo, Burbom Vermelho, Semperflorens and Geisha cultivars grown under photoperiod of 12 and 18 hours. Vegetative growth was intensified by 18 hours of light. Flowering occurred more intensely in long day treatment. The data available indicate that induced coffee plants may keep the flowering capacity independently of day length. It is suggested that the age of the coffee branch tissues play an important rôle to the flowering process.