Abstract: In order to select materials for the guide rod and guide base friction pair of a certain type lock mechanism, the friction and wear performance of the friction pair of 2A12 aluminum alloy in rolling, solid solution, and solid solution and aging states against aged 17-4PH stainless steel under dry friction and grease-coated friction conditions was investigated. The results show that the tensile strength and microhardness of the 2A12 aluminum alloy in the rolling state were higher than those in the solid solution state and solid solution and aging state, but much lower than those of aged 17-4PH stainless steel. The average friction coefficient of the 2A12 aluminum alloy in the rolling state against 17-4PH stainless steel and the average volume wear rate of the aluminum alloy under grease lubrication conditions were significantly lower than those under dry friction conditions, and lower than those of 2A12 aluminum alloy in the solid solution state and solid solution and aging state under the same lubrication conditions. Under the two lubrication conditions, the wear mechanism of the three-state aluminum alloy was mainly abrasive wear, supplemented by adhesive wear, while the wear mechanism of the stainless steel was slight abrasive wear. The pairing of the 2A12 aluminum alloy in the rolling state and the aged 17-4PH stainless steel could be applied in the lock mechanism, and the friction and wear stuck could be reduced by coating grease.