A fiber structure with a circularly polarizing property is proposed. The fiber consists of a round core and a triple-lobe stress region in the cladding, which is compatible with single-mode fibers, and it can be fabricated using conventional metal chemical vapor deposition processes. By coating a layer with a high-refractive index, the twist pitch required for resonant coupling is increased to hundreds of micrometers, and the mature pit-in-jacket drawing technique can be used. The polarization filtering properties of the fabricated circularly polarizing fibers are measured experimentally, showing high distinction ratios in a broad frequency region.