This study assessed the effects of feeding organic selenium (Se) on sperm morphology, motility, membrane integrity and lipidic peroxidation, also on sperm ATP and phospholipid hydroperoxide glutathione peroxidase (PHGPx) in raw semen of mature boars. Twelve boars were divided into three groups: Control, 0.3 ppm sodium selenite, Inorganic, 0.5 ppm sodium selenite and Organic, 0.5 ppm Se yeast for 11 weeks. Organic diet presented a higher total sperm number (P<0.05) when compared to the inorganic treatment; however, no difference was observed regarding volume, sperm concentration, number of cells with plasma and/or acrosomal membrane integrity, membrane mitochondrial potential, ATP assay and Se concentration in seminal and blood content. Also, no difference was observed on motility parameters, sperm morphology and membrane peroxidation, however, PHGPx was influenced (P<0.05) in organic treatment. Thus organic Se feeding influenced none of the analyzed seminal characteristics in raw semen, except for PHGPx and total number of sperm.