Egg yolk is a common additive for sperm cryopreservation extender to protect sperm membrane against cold shock. It is generally accepted that LDLs present in egg yolk are responsible for its protective role during the cryopreservation process. In recent years, arguments concerning the presence of cryoprotective antagonists in egg yolk had reinforced interest to use LDL extracted from egg yolk in the extenders. Some authors believe that the addition of detergent to extender may improve motility, acrosomal integrity, and fertility capacity of spermatozoa. Recently, many antioxidants have been used as supplements in extenders for cryopreservation of sperm with beneficial effects. It is reported that LDL extraction process may reduce or eliminate egg yolk antioxidants. The aim of present study was evaluation the protective effects of egg yolk in combination with sodium dodecyl sulfate (SDS), lyophilized low density lipoproteins and four levels of ethanolic extract of clove bud (0, 35, 75 and 115 µg/ml) in ram semen cryopreservation diluents. Semen samples were collected from three mature Lori-Bakhteyari rams twice a week during the breeding season. The semen samples were diluted with experimental freezing extenders. The motility, viability and plasma membrane integrity were evaluated as the most important parameters of sperm after cooling and thawing. All data were analyzed using the generalized linear model procedure (Proc GLM) of SAS (Version 9.0). The least square means (LSM) were compared using t-test. In general, adding SDS to egg yolk had the best performance in motility parameters, viability and plasma membrane integrity before and after freezing (p 0.05). Eight percent of lyophilized LDL had lower performance than that the control group (15 % egg yolk) before freezing (p 0.05), but it had the same performance after freezing stage. Supplementation of 35 and 75 µg/ml of clove bud extract in extenders clould inhibite the deleterious effects of ROS on ram sperm before semen cryopreservation but the level of 115 µg/ml had toxic effect on sperms. Our results showed after cryopreservation, the optimal amounts of clove bud extract for sperm motility, viability and plasma membrane integrity was 75 µg/ml. It was concluded that the protective function of the low density lipoprotein occur during the freezing and thawing process. Also some steps of the lyophilization process (freeze dry) may reduce the protective capacity of the natural LDL and the amount of antioxidants needed during cooling is lower than during freezing. Keywords: Low density lipoprotein, surfactant (Sodium Dodecyl Sulfate), Antioxidant, Clove, Semen cryopreservation