This paper presents a method for trapping beads and cells using a single-beam optical tweezer and a Fresnel zone plate integrated with a microfluidic chip. The experimental results show that a laser power of 2.4 mW is sufficient to trap 3-mu m-diameter polystyrene beads, while a laser power of 1.5 mW is sufficient to trap individual Jurkat cells. The Fresnel zone plate developed in this study has many advantages, including a small size, a straightforward fabrication process, and a simple integration with microfluidic chips. Consequently, it provides an ideal solution for the trapping of a wide range of biological cells for analysis purposes. (C) 2011 The Japan Society of Applied Physics