Recent Studies have investigated the influence of the resource factor on the quality of secondary education (QSE) in Nigeria. However, the research on the resource factor as a predictor of quality of secondary education in rural communities of Southwestern Nigeria remains scanty. This study, therefore, investigated the contributions of the resource factor (RF: Resource Adequacy-RA and Resource Utilization-RU) to QSE in rural communities of Southwestern Nigeria (RCSN). The study was located within a pragmatic paradigm that incorporated the convergent parallel design in the collection, analysis and interpretation of the qualitative and quantitative data. The multi-level mixed methods sampling technique was adopted in selecting 467 secondary school graduates, while total enumeration technique was adopted in selecting 134 teachers. Six participants for the Key Informant Interviews comprised three principals and three senior officials from the Teaching Service Commission and Ministry of Education from three selected states in southwestern Nigeria. Two research questions were raised, and one hypothesis was formulated for the study. Two research instruments, namely, the Secondary School Graduate Aptitude Test (SSGAT) and Resource Factor Teachers’ Questionnaire (RFTQ), with reliability coefficients of 0.715 and 0.853, respectively, were used for the study. Quantitative data were analyzed using descriptive statistics and Pearson Product Moment Correlation, while qualitative data were analyzed with content analysis. The resource factor with resource adequacy (x=2.50) and resource utilization (x=2.77) influenced QSE. The resource factor (r=0.75) had a negative significant relationship with QSE. The study affirmed that addressing resource inequality in rural communities is urgently required to stem the ebbing tide of quality secondary education in Nigeria.