We proposed a method to guide micro-particles within a millimeter region. A cylindrical mirror is used to create an optical line segment for guiding particles. In order to increase the numerical aperture, Polydimethylsiloxane (PDMS) is poured on the cylindrical mirror. At the top of the PDMS layer, a fluidic channel is fabricated. As a collimated laser beam is incident on the cylindrical mirror, the laser beam is tightly focused and is transformed into a line-shaped pattern in the fluidic channel. In this way, a simple and cost-effective optical guiding system can be achieved.