This study examined the use of social media platforms as a predictor of knowledge sharing among librarians in Nigerian academic libraries. The study was guided by objectives to identify the social media platforms used by librarians, determine the extent of their use for knowledge sharing, and examine the predictive influence of social media platform use on enhanced knowledge sharing for service delivery. The study adopted a survey research design. The population comprised 601 librarians from 12 selected federal university libraries in Nigeria, and a sample of 240 librarians was determined using the Taro Yamane sample size determination table. Stratified random sampling was used to ensure proportional representation of librarians. Data were collected using a structured questionnaire and analyzed using descriptive statistics and regression. The findings revealed that librarians frequently used social networking platforms such as Facebook (71.8%), WhatsApp (67.0%), Pinterest (70.5%), and LinkedIn (48.5%), as well as content-sharing platforms such as YouTube (48.9%), for knowledge sharing. The study also found that social media platforms facilitated the sharing of tacit and explicit knowledge. The regression analysis showed that social media platform types and utilization significantly predicted increased knowledge sharing among librarians for service delivery (F (3, 117) = 134.998, p = .000, R2 = 0.776). The study concluded that social media platforms are significant predictors of knowledge sharing in academic libraries in Nigeria. It is recommended that academic libraries implement social media policies and provide technological support to enhance knowledge sharing.