Adequate supply of dietary protein in regular diet is an important element of a proper nutritional status as it functions in the regulation of metabolic profiles signaling the reproductive axis. Reports have highlighted the association of the amount of protein in the diet to the functioning of hypothalamic-pituitary-testis axis, however its intragenerational effects are yet to be adequately explored. The study aims to analyze the effect of protein deficient diet on parameters associated with male infertility from one generation to another. Female rats in four (4) groups (n=10) were fed different ration of protein in their diet (PD) as formulated: 21%PD, 10%PD, 5%PD and control diet (rat chow), through gestation and lactation to first and second generations, while the male offspring sustained on the maternal diet after weaning were used for analysis. Sperm morphology and motility were evaluated using a light microscope and a computer-assisted semen analysis. The percentage of motile spermatozoa, morphological characteristics and histology in the deficient groups (5%, 10%PD) appeared normal as compared to control in the first generation, showing an adaptive response while second generation was presented with significantly altered fertility parameters of the male offspring. It is suggested that in a deficiency status especially at the critical phase of development, certain deleterious effects which may be adaptive or phenotypic can serve to reduce the fertility efficiency in the male offspring at both F1 and F2- generation.