The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5mg/kg Se, group 3 (G3) supplemented with 10mg/kg Se, group 4 (G4) supplemented with 15mg/kg Se and group 5 (G5) supplemented with 20mg/kg Se. For each group, there was an adjustment period of 14days. The experimental period was 350days. Every 56days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p>.05). Sperm morphology was different between treatment groups, the G1 (0mg of selenium) had the highest percentage of major defects (11.11±1.11a ; p<.05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.