Poor oral health plagues those who are economically disadvantaged and it is older people who are particularly vulnerable. Healthcare professionals, notably nursing staff, can contribute to the reduction of oral health disparities in older men and women. The purpose of this study was to describe an oral health education program and evaluate its effect on oral health knowledge of nursing staff serving economically disadvantaged older people in a religiously affiliated nursing home. The study was structured by a one-group pretest-posttest design to determine whether a change occurred in the oral health knowledge following participation by nursing staff in an oral health education program. Knowledge of Oral Health (KOH) questionnaire, used as both pretest and posttest, was developed to achieve the purpose of the study and knowledge improved significantly. The KOH posttest displayed overall higher scores (M = 7.50, SD = 1.701) than the pretest scores (M = 5.40, SD = 1.569). The KOH score increased by an average of 2.10 points with SD = 1.619 and 95% confidence interval, 1.342, 2.858. The intervention effect was large and statistically significant, t(19) = 5.801, p < .001. Future research should be directed toward refining the KOH questionnaire, determining its application internationally, and directing the oral health education program to include not only nursing staff but older people as well.