Real Nullstellensatz is a classical result from Real Algebraic Geometry. It has recently been extended to quaternionic polynomials by Alon and Paran [1]. The aim of this paper is to extend their Quaternionic Nullstellensatz to matrix polynomials. We also obtain an improvement of the Real Nullstellensatz for matrix polynomials from [5] in the sense that we simplify the definition of a real left ideal. We use the methods from the proof of the matrix version of Hilbert's Nullstellensatz [6] and we obtain their extensions to a mildly non-commutative case and to the real case.Recall that an ideal I of a commutative ring R is real if for every a 1 , . . . , a k ∈ R such that a 2 1 + . . . + a 2 k ∈ I we have a 1 , . . . , a k ∈ I. The smallest real ideal that contains a given ideal J is called the real radical of J and it is usually denoted by rr √ J.1.2. Quaternionic polynomials. In [1], Theorem A was extended to quaternionic polynomials. Their results are summarized in subsections