Objective To observe the expression of phospho-calcium kinase II ( p-CaMKII) in the dorsal root ganglia (DRG) of diabetic rats with diabetic neuropathic pain (DNP). Methods 1) Twenty-one healthy male Sprague- Dawley rats were administered a large dose of streptozotocin ( STZ) to establish the DNP rat model. Changes in Paw Withdrawal Latency ( PWL) were observed before modeling ( Base), 7 days after modeling ( Day 7), 14 days after modeling (Day 14), 21 days after modeling (Day 21), and 28 days after modeling (Day 28). Rat L4-L6 DRG were used at each time point. p-CaMKII positive cells on L4-L6 DRG were detected by immunofluorescence assay. 2) Twenty rats were randomly divided into Control+normal saline (Control+NS), model+normal saline (DNP+NS), and model+CaMKII inhibitor KN93 groups (DNP +KN93). At 14 days after STZ injection, the DNP +KN93 group was administered KN93 solution, and the other two groups were injected with the same volume of NS. Results 1) Compared with the normal group, the Day 7 PWL of the DNP model group did not change significantly, and the Day 14, Day 21, and Day 28 PWL decreased significantly. Immunofluorescence result showed that compared with the control group, p-CaMKII positive cells on L4 DRG of DNP rats were significantly increased at 7, 14, 21, and 28 d after STZ injection. p-CaMKII positive cells on L5 and L6 DRG were also increased significantly, and the difference between control group was statistically significant. 2) Before KN93 intervention, there was no significant difference in PWL between the DNP+NS and DNP+KN93 groups. After 1 hour of intervention, the PWL was significantly increased in the DNP+KN93 group compared with the DNP+NS group. Conclusions The production and maintenance of diabetic neuropathic pain is related to the upregulation of p-CaMKII expression on DRG neurons. An injection of the CaMKII inhibitor KN93 in the hind paw of rats inhibited thermal hyperalgesia.