Eremomastax speciosa is widely used in ethnomedicine for various purposes, but the possible toxic effects on fertility parameters following sub-acute intake have not been studied. 36 immature male and 36 adult female rats were each divided into four groups of nine rats (Control, Extract 250, 500, 1000 mg/kg). Males received extract for 60 days and females for 14 days. From day 15, a fertility study was done by cohabiting one male with one female from each corresponding group for 10 days. In males, plant extract (250-1000 mg/kg; p< 0.01) reduced testicular and spleen weights, increased epididymis weights (250-500 mg/kg; p<0.001) and increased spermatozoa density and motility (at 250 mg/kg). In females, the extract did not influence number of uterine resorptions and number of live offspring compared with controls. Red blood cell count significantly increased (p<0.01) in males and significantly decreased (p<0.05) in females compared with controls. Simultaneous treatment of male and female rats with the extract of E. speciosa does not negatively affect reproductive performance. E. speciosa may be safely used by reproducing couples at the dose of 250 mg/kg for the management of various disease conditions without the risk of reproductive toxicity.