A number of herbal drugs are advocated in the traditional Ayurvedic literature for the improvement of overall sexual function. Young roots of Bombax ceiba Linn. (Fam. Bombacaceae) [correction added after online publication 1 August 2011: the family of Bombax ceiba was incorrectly mentioned as Orchidaceae. It has been corrected to Bombacaceae] also known as Semal Musli are used traditionally in Indian subcontinent as sexual stimulant. Its juice is considered nutritive and restorative tonic. Lyophilised aqueous extract of roots was studied for effect on sexual behaviour and spermatogenesis in male albino rats. Administration of 100 mg Kg−1 body weight of aqueous extract influenced the five parameters evaluated in vivo. Sexual behaviour analysis in the presence of a female rate, serum testosterone level, anabolic effects, epididymal sperm count and seminal fructose level were the parameters evaluated. In B. ceiba extract-treated animals, a gain in body and sexual organ weights was observed. Mount, intromission and ejaculation frequencies were significantly improved (P < 0.05). An increase in serum testosterone levels was also observed, but it was not statistically significant (P > 0.05). Seminal fructose content and epididymal sperm count were significantly improved as well. Penile erection index was also higher compared to control group animals. Hesitation time was significantly reduced (P < 0.01), and copulatory rate was doubled in treated animals compared with control group animals.