Abstract: Based on drop to idle（DTI）regeneration characteristics of diesel particulate filter（DPF）, an evaluation method for the amount of soot loading and the target regeneration temperature was introduced. DPF DTI regeneration testing was carried out in a diesel engine, in which DPF soot was loaded under non-road transient cycle（NRTC） operation and the regeneration temperature was controlled by in-cylinder post injections. The internal temperature of the DPF substrate during DTI regeneration process was measured at the soot loading amount of 8 g/L and different regeneration temperatures. At the target temperature of 600 ℃, the internal temperature of the DPF substrate during DTI regeneration was measured at different soot loading amounts. Under NRTC operating conditions, the engine row particulate matter（PM） and the PM concentrations in the upstream and downstream of the DPF were obtained by a AVL MSS-483 smoke meter. Furthermore, the PM filtration efficiency after DTI regeneration was also obtained. The results show that at the soot loading amount of 8 g/L, the maximum internal temperature of the DPF increases with the reduction of regeneration temperature, and the risk of DPF damage caused by DTI regeneration increases. The PM filtration efficiency of the DPF before regeneration is as high as 99.95%, but decreases to 97.10% after the DTI regeneration. When the target regeneration temperature is 600℃ and the carbon load is 12 g/L, the peak temperature in the DPF exceeds 1 500 ℃, leading to a damage of the silicon carbide carrier and a reduction of the PM filtration efficiency to 87.30%. In other soot loading amount cases, the DPF substrates are not damaged.