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In order to launch the lunar soil sampling test, a novel parallel mechanism of three degrees of freedom was designed and analyzed for the position and orientation adjustment. According to characteristics in movement of the mechanism, the freedom degree of mechanism was calculated by the modified K-G (Kutzbach-Grübler) formula after the analysis and calculation, the mechanism has a total of 3 degrees of freedom with 2 rotation and vertical movement, and the inverse solution of the kinematics problem was solved by adopting the closed vector method. The evaluation indexes of performance in velocity, acceleration and dexterity of the mechanism were established. A multi-objective genetic algorithm was proposed to optimize the structural parameters of the mechanism based on the performance of velocity and dexterity. The working space and singularity as well as performance in velocity and dexterity of the mechanism could be obtained after analyzing the optimized structural parameters. Results showed that the performance in velocity was excellent under the condition that α and β of the moving platform were moved in the range of -0.35~0.35rad and the maximum value of the velocity performance index of the sampling test mechanism will appear in this range. The results also showed that the singularity would not appear when the performance indexes in dexterity were in the range of [4,5] and the mechanism had good movement performance and the operation velocity of the attitude of the moving platform in the characteristic direction and be satisfied. All the analysis results proved that the mechanism can meet the requirements of lunar soil sampling test and it had certain reference value for development of lunar soil sampling test.