A structure configuration scheme for a hybrid type virtual axis machine tool is proposed in this paper. The scheme utilizes a 4 DOF spatial parallel mechanism as main feed mechanism

with assistance of a dual-direction movable worktable

multi-coordinates NC machining can be realized. Closed form equations of forward displacement analysis for main feed mechanism are established. Workspaces of main feed mechanism and hybrid type virtual axis machine tool are analysised based on surface analysis method. Numeric examples are given for illustration.