This study investigated the influence of library marketing on patronage among faculty members in federal polytechnics in South-West, Nigeria. The study was anchored on two relevant theories which are; Expectation Confirmation Theory and Social Marketing Theory. Descriptive survey design was employed. The population comprised all the academic staff on full-time appointment in federal polytechnics in South-West, Nigeria totaling 2,393. Two-stage sampling technique was employed to select 957 which formed the sample size of the study. The instrument used for data collection was an adapted questionnaire validated using Cronbach alpha in which an overall reliability coefficient of 0.975 was obtained. A total of 871 valid copies of questionnaire which were retrieved from 957 copies administered to the respondents representing 91% response rate, were used for data analysis. Data on research questions were analysed using descriptive statistics while hypothesis was tested at 0.05 level of significance using linear regression analysis. Findings revealed low level of library patronage among the faculty members ( ̅ ); minimal adoption of marketing strategies by the polytechnic libraries ( ̅ ), and a significant positive influence of marketing on library patronage (R2 = 0.349; calculated value = 0.000 >α-level =0.05). The study concluded that library marketing is a significant predictor of patronage among faculty members in federal polytechnics in South-West, Nigeria. Consequently, it is recommended that polytechnic library managers and staff should continue to design and implement effective marketing strategies that could efficiently communicate the resources, services and facilities to the faculty members using relevant media and channel.