Cryopreservation is a process where a sample, e.g. cells or tissue, is preserved by cooling to sub-zero temperatures, usually -196°C. Upon freezing these materials, ice crystals form, which eventually results in cell death. In order to reduce the formation of ice crystals, cryoprotectants are added to the storage solution. Current cryoprotective agents have several weaknesses, making the development of cryoprotective agents with advanced properties of great interest. In this study, two possible non-penetrating cryoprotectants termed Dextran Sulphate Sodium Salt 80 (DSSS 80) and Dextran Sulphate Sodium Salt (DSSS 140), were developed. The cryopreservative effect of DSSS 80 and DSSS 140 was studied on human spermatozoa regarding cryorecovery, using a simple cryopreservation procedure. Moreover, the new compound’s cryoprotective properties were compared to conventional types of dextrans, which in previous studies have proven effective. The percentage of sperm motility was assayed before freezing by the optical microscopic method using a haemocytometer as counter chamber. After thawing, the cells were stained with trypan blue and post-thaw motility was determined. It was found that all sperm cells lost their motility, regardless cryoprotectant, concentration or in the absence of dextrans, which indicated that the applied cryopreservation was unfitting. Thus, since the method used in study was not optimal for cryopreservation of sperm cells, it was not possible to determine whether DSSS 80 or DSSS 140 display cryoprotective properties or not, nor if they are superior to conventional types of cryoprotectants.