Abstract: In order to testify the mechanical condition of harvesting castor, the tensile properties and bending properties of capsule-peduncle node, stem-peduncle node and different growing parts of stem were tested. The results showed that the tensile force and tensile strength of capsule-peduncle node were 3.31-6.74 N and 3.48-8.31 MPa at ripening stage, 1.90-4.15 N and 2.42-5.28 MPa at harvesting stage. The tensile force and tensile strength of stem-peduncle node were 15.78-37.07 N and 19.70-34.66 MPa. The tensile force, elastic modulus and tensile strength of stem bark were 56.99-130.42 N, 160.99-203.80 MPa and 28.50-65.21 MPa. The bending force, bending section modulus and bending strength of stem were 15.20-91.04 N, 31.53-173.07 MPa and 19.27-21.04 MPa. The analysis results indicated that there were significant differences between the connection strength of capsule-peduncle node, connection strength of stem-peduncle node, stem tensile strength and stem bending strength, which proved that capsule-peduncle node was easiest to fracture in the process of picking, followed by stem-peduncle node. By reasonably designing the working parameters of picking parts, the harvester can just pick the castor capsule without destroying the stem.