Abstract-- This paper considers when a discrete-time periodic non-homogeneous system can be transformed to a time-invariant one by using regular linear mappings of state variables, inputs and outputs, respectively. The problem on a homogeneous system has been already solved as discrete-time Floquet transformation, and also the similarity classes of Floquet transformations have been characterized. Those previous results are used to derive some conditions on transformability of non-homogeneous systems.