The noncontact control method with laser light pressure enabled us to trap and manipulate the particles of micrometer by laser trapping. This technique has been widely applied as one that can manipulate the particles in the nondemolition and noncontact state. In recent years, technical development to unveil the particle character of laser has been made in the field of cell technology, gene technology and ultramicrofabrication. And so, the experiment to trap and manipulate the particles in fluid with Ar laser is done to find optimal operation condition in noncontact movement of particles. Concludingly, the trapping force by laser irradiation depends on the particle properties.