A collection unit includes an exhaust conduit providing a path through which a process gas flows, a trap installed in the exhaust conduit, and a collection line connected to the trap. The trap has an inlet through which particles in the process are introduced into the trap, and the collection line penetrates a portion of the exhaust conduit to extend toward an outside region of the exhaust conduit. An apparatus including the collection unit and a method for collecting particles using the same are also provided.