We design a compact triplexer based on two-dimensional (2D) hexagonal lattice photonic crystals (PCs). A folded directional coupler (FDC) is introduced in the triplexer beside the point-defect micro-cavities and line-defect waveguides. Because of the reflection feedback of the FDC, high channel drop efficiency can be realized and a compact size with the order of micrometers can be maintained. The proposed device is analyzed using the plane wave expansion method, and its transmission characteristics are calculated using the finite-difference time-domain method. The footprint of the triplexer is about 12×9 μm, and its extinction ratios are less than –20 dB for 1310 nm, approximately –20 dB for 1490 nm, and under –40 dB for 1550 nm, making it a potentially essential device in future fiber-to-the-home networks.