The effects of changes in temperature on physiological and biochemical activities of Ino were studied in the laboratory to better understand the thermal tolerance mechanisms of abalone. Abalone were transferred abruptly from a rearing temperature (15℃, control temperature) to 5℃, 10℃, 20℃, or 25℃. Other groups of abalone were acclimated to different experimental temperatures (5℃, 10℃, 20℃, and 25℃) by gradually increasing or decreasing seawater temperature (0.5℃/12 h). Then, oxygen consumption and ammonia excretion rates of Ino were measured, the activities of superoxide dismutase (SOD), catalase, acid phosphatase and lysozyme (LSZ) in the digestive gland were determined, and Cu/Zn-SOD gene expression levels in hemocytes and muscle were determined. The results showed that oxygen consumption and ammonia-N excretion rates of Ino increased gradually with an increase in water temperature and peaked at 20℃. The rates of oxygen consumption and ammonia-N excretion in the 25℃-acute temperature change treatment were significantly higher than those in the gradual treatment (<0.01). Moreover, significant differences in the abalone O/N ratio were observed between the acute and gradual temperature change treatments at 5℃ and 10℃ (<0.01). SOD, catalase, acid phosphatase, and LSZ activities increased significantly in abalone exposed to high temperature (25℃) for 72 h and reached the maximum at 3 h or 6 h (<0.01). However, a significant decrease in LSZ activity was found in abalone in the 5℃-acute temperature change treatment and reached the lowest level after 9 h (<0.01). Significantly up regulated Cu/Zn-SOD gene expression was also observed in hemocytes and muscle in abalone from the different temperature treatments (H. discus hannai Ino were significantly affected by temperature. These data provide valuable insight into the possible mechanisms of abalone summer mortalities and will serve as a theoretical basis for healthy breeding of abalone.