In the paper, we describe the structure of colloidal photonic crystal microstructure fiber and investigate the propagation characteristics using the finite-difference time-domain method. A structure model is eastablished to simulate the transmission spectra and propagation field distributions under different wavelengths. Experimental system is built to measure the transmission spectrum of fabricated colloidal photonic crystal microstructure fiber. Experimental result is in good agreement with numerical result. The propagation field distribution result shows that the colloidal crystal changes the propagation mode of optical fiber under different wavelengths.