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Accurate measurement of tillage resistance for cultivate component is critical. The related resistance testing device has complex structure, high maintenance cost, lack of overload protection and difficulty in collection in farmland. Aiming at the problems of the related resistance testing device, the tillage resistance testing device (TRTD) for sliding cultivate component was designed. TRTD consisted of component library, torsional spring, rotation axis, positioning plate and encoder. The force analysis of double-wings subsoiler was carried out. A measurement method of tillage resistance was established which contained the relationship of correction factor k as a function of spring corner θ, tilling depth H, tilling speed v, soil bulk density ρ and subsoiler structure parameters. In order to evaluate the TRTD, a soil bin contrast test with traditional testing device (TTD) was conducted under six tillage condition treatments. The test results showed that the mean and variance of the measured sample from both testing devices had no significant difference. The results of precision analysis showed that the maximum relative error of TRTD was 1.34% compared with TTD. The results of fluctuation analysis showed that the fluctuation amplitude of TRTD was similar with that of TTD and both relative deviations were not more than 5%. TRTD met the requirement of accuracy and stability and possessed the function of overload protection as well as providing condition for acquisition of tillage resistance.