Women's Missionary Union oversees the mission education of the women, young women, girls and preschoolers (boys and girls) at Oak Grove.
WMU’s tasks include teaching missions; engaging in mission action; supporting world missions through praying and giving; and providing and interpreting information regarding the work of the church and denomination.
The girls and preschoolers meet on Wednesday nights. The Baptist Young Women meet on the first Thursday night of each month at the home of one of the group's members. The Celebrate Life group meets during the daytime.
WMU began at Oak Grove in the early 1940s. WMU promotes the mission offerings of the church--Annie Armstrong North American Mission Offering, Eliza Broadus State Mission Offering, and the Lottie Moon International Missions Offering.