  The global defensive $k$-alliance is a very well studied notion in graph
theory, it provides a method of classification of graphs based on relations
between members of a particular set of vertices. In this paper we explore this
notion in zero-divisor graph of commutative rings. The established results
generalize and improve recent work by Muthana and Mamouni who treated a
particular case for $k=-1$ known by the global defensive alliance. Various
examples are also provided which illustrate and delimit the scope of the
established results.
