Let $B$ be a ring with 1, $G$ an automorphism group of $B$ of order $n$ for some integer $n$ invertible in $B$, $C$ the center of $B$, and $B^G$ the set of elements in $B$ fixed under each element in $G$. Then, $B$ is called an Azumaya automorphism extension of $B^G$ with automorphism group $G$ if $B\cong B^G\otimes_{C^G} V_B(B^G)$ as Azumaya $C^G$-algebras under the multiplication map. Some characterizations of an Azumaya automorphism extension are given and its subextensions arising from subgroups of $G$ are also investigated.