Incidents of violence among intimate partners remains an increasing concern in Nigeria. More disturbing is the fact that some women still justify acts of violence (particularly, wife-beating) from their partners. The purpose of this study is to investigate the impact of spousal demographic gap and other specific demographic constructs in explaining women’s justification of wife-beating. The study is based on married or cohabiting women sampled in the 2018 Nigeria Demographic and Health Survey. The study shows that, overall, 31% of women justified wife-beating. The proportion of women justifying wife-beating ranges from as low as 1% to as high as 89% across the 36 States. Using Binary Logistic Regression, partners’ age difference was not a significant predictor. However, when a woman’s education level is at par (OR = .844, p < .05) or higher than that of her partner (OR = .726, p < .000), she is less likely to believe that a man is justified to beat his wife under any circumstances. Other factors explaining the justification of wife-beating among married and cohabiting women are economic status, place of residence, employment status of partners, and women’s involvement in decision-making. The findings reveal the association between spousal demographic gap and women’s justification of wife-beating. Programs that address individual and structural factors promoting justification of wife-beating become necessary.