Cryopreservation of giant grouper sperm Epinephelus lanceolatus (Bloch, 1790) is a technique to overcome the problem of unsynchronized spawning of grouper. Glycerol and palm dates were used as a cryoprotectant. The aim of this study was to determine the effect of palm date concentrate and glycerol on motility, viability, and abnormality 48 hours postcryopreservation and the ability of fertilization using giant grouper sperm postcryopreservation with tiger grouper (Epinephelus fuscogutatus ). The palm date concentrations used in this study were 0%; 5%, 10%, 15%, 20%, and 25%. The ratio between sperm and diluent solution was 1:9. The extender used in this study is a marine fish Ringer solution. Fresh sperm were evaluated macroscopically (volume, pH, color, and odor) and microscopically (motility, viability, and abnormality) to test the sperm feasibility for cryopreservation and fertility ability by calculating the percentage of fertilization. Sperm was stored in a freezer -200C for 48 hours. Spermatozoa postcryopreservation were used to fertilize tiger grouper eggs. Based on the results of statistical tests of one-way ANOVA followed by the Tukey Test, it was shown that palm date concentrate with various concentrations had an average value that significantly affected motility sperm and abnormality after cryopreservation (P<0.05), but had no significant effect (P>0.05) to viability. However, the results of fertilization with tiger grouper showed a significant effect (P<0.05). The best results were shown in the concentration of 10% palm date concentrate with a percentage value of 76.70 ± 1.54% in motility sperm, the value of the viability percentage is 77.67 ± 5.78%, and the value of fertilization ability is 66.25 ± 3.23%, with an average percentage value of abnormality is 21.53 ± 0.84%."