Cutting tools with different rake angles were used to perform large strain cutting of pure copper, and the obtained ultrafine grained pure copper chips were annealed at different temperatures. The scanning electron microscope (SEM) and Vickers hardness tester were used to detect, and the effects of different rake angles and annealing temperatures on the microstructure and mechanical properties of ultra-fine grained pure copper chips were analyzed. The results show that the average chip grain size is 0.3 μm and the hardness is 160 HV after large strain cutting with 0° rake angle tool, when the annealing temperature is 200~280 ℃, the grains are in the recovery and recrystallization stage and have good thermal stability, when the annealing temperature is higher than 280 ℃, the grain size increases significantly and the hardness decreases significantly; after large strain cutting with -20° rake angle tool, the average chip grain size is 0.2 μm and the hardness is 168HV, when the annealing temperature is 200~320 ℃, the grains are in the recovery and recrystallization stage and have good thermal stability, when the annealing temperature is higher than 320 ℃, the grain size increases greatly and the hardness decreases significantly; the smaller the rake angle of the tool is, the better the ultra-fine grained pure copper chips thermal stability is; compared with 0° tool rake angle, the ultra-fine grained chips processed by the tool with -20° rake angle have better thermal stability.