In this paper, the authors provide a facile way to fabricate a microstructure fibre by coating a standard optical fibre with a silica inverse opal through a sol-gel co-assembly method. Polystyrene (PS) colloidal suspension of microspheres and a hydrolysed silicate precursor were added to the solvent together. With the evaporation of the solvent, the assembly of a PS colloidal template and the infiltration of voids of the spheres with silica gel were executed simultaneously to form a colloidal composite in a single step. After removal of the sacrificial colloidal template, a cylindrical inverse opal (C10) cladded an optical fibre was obtained. Structural properties characterised by optical and SEM and unique transmission spectra with photonic band gaps reveal the high quality of the silica C10s, which can be used as fibre Bragg grating for optical communications.