The rotary shaft hole centerline of ropeclipping component and the rotary shaft hole centerline of knotter hook are basic design parameters in the D-knotter’s structural design. By establishing space coordinate system, the space angular relationship of those two rotary shaft hole centerlines were described analytically. With the help of differential geometry theory, the numerical analysis conditions of the sport relations between rope-clipping component and knotter hook were established, the influences of related parameters, including k0,k1,α2 and d5 on the action of rope-sending and rope-towing were analyzed. The results showed that action of ropesending and ropetowing would be successful when the values of α2 and d5were 8°and 54mm, respectively. The influences of related parameters, including j2, j1 ,α1 and α3 on the action of ropewinding and ropebiting were analyzed. The results showed that action of ropewinding and ropebiting would be successful when the values of α1 and α3 were 10° and 25°, respectively. Based on the analyzing angle parameter of the D-knotter, the physical model of each part of the D-knotter was obtained by machining. Then the forming performance test of the designed D-knotter and the D-knotter from Germany was carried out, totally 200 experiments were carried out to observe the effect of tying rope on the two kinds of D-knotter. The experimental results showed that the rope structure was basically the same from the two D-knotters, and the knotting rate of the two kinds of D-knotter was all 100%. The experimental results showed that spatial angle parameters of rope-clipping component and knotter hook were correct, and the analytical model was accurate and reliable. The model could be used for the parametric design of D-knotter.