Photonic devices based on polymer materials have been fabricated mainly by using conventional lithography and etch processes. However, the fabrication method through these processes is complex and expensive. We fabricated 1310/1550 nm demultiplexer using an embossing technique, which was able to reduce the fabrication cost. The mold is an elastomeric polydimethylsiloxane (PDMS) and resists used as the core and the cladding layers are ZP 51 (ChemOptics) and ZP 49' (ChemOptics), respectively, which are thermal curable polymers. The fabrication process is summarized as follows: (1) manufacturing the photoresist master by lithography process, (2) forming the PDMS mold from the master, and (3) replicating the device using the mold. There is no observation of any noticeable pattern difference between the master and the replica in microscaled dimension. In this work, we also investigated the durability of a PDMS mold for mass production. and successfully fabricated the 50th replica with the same mold. The replicated device was measured by the laser source and the charge-coupled device camera. (c) 2006 American Vacuum Society.