This study was designed to compare the addition of lecithin (LC) and lecithin nanoparticles (LC-NPs) to a semen extender (control group – egg yolk, EY) during a storing period in relation to its effectiveness on buffalo sperm cryopreservation. Ejaculates were collected from six mature, healthy Egyptian buffalo bulls using an artificial vagina, and diluted with nine extenders. LC-NPs and LC were tested at concentrations of 0.25, 0.5, 1.00, and 1.50 μg/ml compared to the egg yolk extender. The results indicated an overall enhancement in sperm quality: increased progressive motility and improved hypo-osmotic swelling test (HOST), reduced instances of dead sperm, abnormal morphology and chromatin damage in the LC-NPs group compared to both LC and the control groups (P < 0.05), apart from group 0.25 μg/ml. Furthermore, LC-NPs demonstrated superior viability at a concentration of 1 μg/ml. This concentration exhibited lower rates of early and late apoptotic events, as well as reduced necrosis compared to lower concentrations. The results showed significantly increased (P < 0.05) antioxidant indices, including superoxide dismutase (SOD), glutathione peroxidase, and total antioxidant capacity, with the inclusion LC-NPs, particularly notable at concentrations of 1.00 and 1.50 μg/ml, surpassing the effects observed in other groups. In contrast, the levels of malondialdehyde decreased significantly (P < 0.05) with LC-NPs, particularly at 1.00 μg/ml in comparison to the LC and control groups. Moreover, the fortification of cryopreserved spermatozoa with 1 or 1.5 μg/ml LC-NPs resulted in the preservation of acrosomal and plasma membrane integrity, as well as normal ultrastructure. So, the addition of LC-NPs, particularly of 1 or 1.5 μg/ml, significantly enhanced sperm quality by improving antioxidant indices, reducing apoptosis, and preserving ultrastructure integrity of buffalo sperm after the post-thawing process.