The chemical etching method is used to reveal dislocations produced by indentation on silicon single crystal specimens. Edge (or 60°) dislocation velocities are measured under different shear stresses and at different temperatures (700-900℃). By assuming that the motion is thermally activated, the corresponding activation energy is obtained to be ～2.94 eV. Velocities of edge (or 60°) dislocations and screw dislocations at 900℃ are compared, the latter being smaller. Measurements of dislocation velocities on different specimens show the retarding effect of as-grown dislocations. Dislocation multiplication is observed from as-grown dislocations and from grain boundaries. Dislocation velocities in process of multiplication are measured. Factors affecting the measured values of dislocation velocities are discussed.