There were many cases of Grampus griseus stranding in Hainan Province in recent years. On June 12, 2021 and October 11, 2022, one Grampus griseus (A and B) was found stranded in the waters of Dahua Jiao, Wanning Hele Town, Hainan Province, and Mulan Bay, Puqian Town, Wenchang City, Hainan Province, respectively. Due to severe injuries and illness, the dolphin died at 14:25 on June 14, 2021 and November 14, 2022, respectively. In this study, blood routine and blood biochemical indexes of two dolphins were detected, and the cause of death was analyzed by anatomy. The results showed that the subcutaneous fat of the two dolphins was thin, and they were all malnourished, and RBC, MCH and MCV in the blood of the two dolphins were higher than the normal range. The post-mortem examination revealed that Grampus griseus B had severe inflammation and bleeding in its internal organs, a large number of parasites in its respiratory and digestive systems, and no food or other foreign matter in its digestive system. The death of Grampus griseus A was caused by complications caused by body surface trauma infection, possibly gastrointestinal inflammation and long-term inability to eat, high malnutrition, heart and liver damage and other causes. Due to a large number of parasites in the respiratory system and digestive system, Grampus griseus B was infected with emphysema, pulmonary hemorrhage, mucous membrane exudation and bleeding, and there are many ulcers. Besides, it showed severe hyperosmolar dehydration, severe hepatitis, nephritis, renal hemorrhage and other multi-organ lesions for a long time after stranding, and finally died of systemic sepsis. In this study, blood routine and blood biochemical indexes of stranded Grampus griseus are detected, and the cause of death is analyzed by pathological autopsy, which provided reference data for the rescue work of stranded dolphins and had high theoretical reference value and scientific research value.