A new type of non-scanning correlation demodulation system based on a new compound optical wedge structure is introduced in order to improve the correlation demodulation resolution of compound fiber Fabry-Perot (FP) sensors. Based on the desired demodulation range of the optical thickness of each cavity of the compound fiber FP sensors along the pixel arrangement direction of the linear array CCD, an air-gap optical wedge structure having different tilt angles and thickness ranges is designed and adopted to achieve the compound synchronous demodulation of multiple FP cavity lengths. The demodulation performance of the designed compound optical wedge structure is simulated and analyzed for compound fiber FP sensors having basal and air-cavity lengths of 600 μm and 80 μm, respectively. Simulation results show that such sensors with multiple FP cavities and different optical thicknesses are demodulated synchronously and accurately using the proposed non-scanning correlation demodulation system based on the compound optical wedge structure. The demodulation resolution for a compound fiber FP sensor can be better than that of a single optical wedge. This conclusion is particularly true for a compound fiber FP sensors comprising cavities with large cavity length differences.