let $r$ be an associative ring with identity and $z^*(r)$ be its set of non-zero zero divisors. the zero-divisor graph of $r$, denoted by $gamma(r)$, is the graph whose vertices are the non-zero zero-divisors of $r$, and two distinct vertices $r$ and $s$ are adjacent if and only if $rs=0$ or $sr=0$. in this paper, we bring some results about undirected zero-divisor graph of a monoid ring ov...