Nishiokitama (西置賜郡, Nishiokitama-gun) is a rural district located in Yamagata Prefecture, Japan.
As of December 2013, the district has an estimated population of 30,443 and an area of 1,224.89 km2.
Okitami County was an ancient place name in part of Dewa Province.
Under the Tokugawa shogunate, the portion which became Nishiokitami district consisted of 116 villages entirely within the area controlled by Yonezawa Domain.
With the establishment of the municipalities system on April 1, 1889, it was organized into one town (Nagai) and 16 villages.