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In order to improve the friction and wear performance of agricultural machinery wheel molds in low-speed and heavy-load operating environments, WC coatings were prepared on GCr15 substrates by using electro-spark deposition technology and ultrasonic vibration composite electro- spark deposition technology, respectively, with GCr15 used in agricultural machinery wheel molds as the object of study. The microhardness, surface roughness, friction and wear performance of the WC coatings were analyzed and tested by using microhardness tester, surface roughness tester, friction and wear tester and three-dimensional white light interference profiler. The results showed that the surface roughness of the ultrasonic vibration composite WC coating was 4.641 μm, which was lower than that of the electro-spark deposition WC coating by about 62%. The microhardness was 1114.6 HV0.025, which was improved by about 15% compared with that of the electro-spark deposition WC coating, and improved by about 67% compared with that of the substrate. The results of the friction and wear test showed that the average coefficient of friction and the wear of the ultrasonic vibration composite WC coating and the electro-spark deposition WC coating were lower than that of the substrate, which indicated that the preparation of the WC coating can effectively improve the friction reduction and wear resistance of the mold. The average coefficient of friction, wear amount and depth of abrasion of the ultrasonic vibration composite WC coating were lower than that of the electro-spark deposition WC coating, which indicated that the ultrasonic vibration composite WC coating had the best friction and abrasion resistance under the condition of heavy load and low speed. The wear amount of the specimen was in a negative correlation with its microhardness, and in a positive correlation with the average coefficient of friction and coating surface roughness.