Abstract: This article presents a matrix-method for calculating the degrees of freedom of the executing(output)member of an industrial robot with specified construction and inspecified situation.Rank of the matrix,consequently the loss of degrees of freedom ofthe output member of the specified mechanism in a specified situation,and its max.and min.degree of freedom can be easily determined by the proposed simple methodinstead of tedious calculation.Tables for determing the peculiar situation and mechanism structure and examples of cclculating degrees of freedom are also given.