Aiming at the demand of intelligent agricultural robots for a wider range of machine vision, a solution of parallel vision table for agricultural robot was introduced. Based on the input and output characteristics of the double rocker mechanism, a new design method of kinematic chain was presented, which can be used to design a decoupled 2DOF parallel mechanism with a fully spherical workspace. Two feasible kinematic chains were derived, i.e. P5R and PRR. Two decoupled 2DOF parallel vision table with a fully spherical workspace were designed based on the above kinematic chains, i.e. RR&P5R and RR&PRR. The displacement relationship of the two mechanisms were established respectively through kinematics analysis. The optimal length ratio of the members of the two mechanisms were obtained respectively through the size optimization. After comparison, the RR&P5R parallel vision table had the better input and output performance. Through statics analysis, the restraining force at each hinge was obtained. Through finite element simulation, the influence of load on the motion accuracy of RR&P5R parallel vision table was analyzed. The result showed that the strength of RR&P5R mechanism met the requirements. However, the displacement deviation of revolute joints of RR&P5R mechanism was large, which was caused by the cumulative elastic deformation of members. 