We construct a three-dimensional deconfinement method which enables us to find new three-dimensional dualities and we apply various techniques developed in the fourdimensional supersymmetric gauge theories, such as product gauge groups and SeibergWitten curves, to the three-dimensional N = 2 supersymmetric gauge theories. The dual descriptions of the three-dimensional N = 2 supersymmetric gauge theories which involve two-index matters, for example, adjoint, symmetric, and anti-symmetric matters without a superpotential can be obtained. These matters are described in terms of the s-confining phases of the supersymmetric gauge theories.