Abstract: In order to make the selection of comminution equipments and process more accurately and reasonably，the popular material comminution properties measured methods in AG/SAG operation at abroad：the JKTech Drop-weight Test method was introduced systemically.The comminution properties that are the impact parameter A and b as well as abrasion parameter T_a in Chengde Iron Ore are determined by using JK Drop-weight Tester and abrasive grinding testing device.By comparing the test results with the data in database，it can be seen that ①the three samples' comminution properties are similar with each other，which meant all the sample belong to the soft and middle-soft ore.②with the crushing energy of 2.5，1.0 kWh/t，the impact resistance decrease with the increase of the particle size.The more the crushing energy is，the more significant the impact resistance decreases.With the specific crushing energy of 0.25 kWh/h，the impact resistance increase with the increase of the particle size.It means that the impact resistance decrease with the specific crushing energy，and the curve slope of t₁₀ & particle size becomes less.③The test results can be successfully applied into calculation of throughput and energy consumption，as well as AG/SAG flow-sheet design and simulation.It indicated that comminution properties by JKTech Drop-Weight Test could not only measure the ore properties，but also lay the foundation for equipment selection and flow-sheet determination.

Key words: Drop-Weight Test, Comminution parameters, AG/SAG