A procedure for the generation of three-dimensional optical vortex-often called an optical black hole-has been reported in this paper. The mask needed to generate such a beam must be three-dimensional one and can be achieved using stack of diffractive-optical-elements. Two different formulas used to produce this three-dimensional vortex and the simulated results show that both the formulas are equally good. This can be used in optical-tweezer to trap a particle at a particular point in space. © 2009 The Japan Society of Applied Physics.