The invention discloses the technical field of subway construction and especially relates to a subway track bed construction ditch model and an operation method thereof. The subway track bed construction ditch model comprises a ditch model formed by splicing multiple model segments and a suspension bracket used for installing the model segments, the suspension bracket is of a long-strip structure and is arranged below a steel rail, one end of the suspension bracket is used for connection with the bottom of the steel rail, the other end is provided with a vertical mechanism used for adjusting the heights of the model segments, and the suspension bracket is provided with a sideslip structure connected with the vertical mechanism to enable the vertical mechanism to perform transverse movement along the sideslip structure. During application, the suspension bracket is horizontally arranged, the ditch model performs height adjustment and transverse adjustment through the suspension bracket, positioning of the ditch model in a height direction and a horizontal direction is realized, and the ditch model is simple in structure, flexible in adjustment, solves the problem of difficulty in transverse adjustment and height adjustment by use of a conventional ditch model, simplifies the construction process, shortens the construction period and saves the construction cost.