  In this paper, we study the competition graphs of $d$-partial orders and
obtain their characterization which extends results given by Cho and Kim
\cite{chokim} in 2005. We also show that any graph can be made into the
competition graph of a $d$-partial order for some positive integer $d$ as long
as adding isolated vertices is allowed. We then introduce the notion of the
partial order competition dimension of a graph and study graphs whose partial
order competition dimensions are at most three.
