We report an experimental study of four-channel frequency division multiplexed fluorescence confocal microscopy (FDMFCM) detection system modulated by holographic polymer dispersed liquid crystal (H-PDLC) Bragg grating array chopper. In the system, fluorescence signal is excited by the exciting light focused on the biological sample, and then is detected. Fourier transform, filtration and demodulation are then carried out to restore the fluorescence signal with a curve of four-channel fluorescence signal intensity versus time. The four-channel FDMFCM system is experimentally set up with 405 nm laser as the excitation light, and the image and intensity information of the fluorescence signal, which are excited from the mouse neural hippocampus cell sample, are successfully detected.