This study assessed the influence of research and development (R&D) activities on managerial entrepreneurial and administrative roles in multinational companies (MNCs) operating in Nigeria. The study was necessitated by the increasing demand for organisations to align managerial capacities with innovation-led strategies as a way of enhancing worldwide competitiveness. Capitalizing on Innovation Diffusion Theory and Resource-Based View (RBV), the study employed an explanatory quantitative approach, employing structured questionnaires to obtain data from managerial personnel in chosen MNCs in Lagos and Abuja. Of the 300 distributed questionnaires, 267 were returned and checked, translating to a 89% rate of response. Partial Least Squares Structural Equation Modeling (PLS-SEM) was employed in data analysis. The findings revealed that R&D processes positively and significantly influenced entrepreneurial tasks (β = 0.803, T = 28.503, p < 0.05) and administrative tasks (β = 0.732, T = 22.660, p < 0.05) of managers, showing that investing companies in R&D provide greater managerial flexibility, innovativeness, and efficiency. The study concludes that R&D is a strategic means of increasing managerial efficiency and organisational sustainability in the competitive business environment of Nigeria. It recommends that MNCs institutionalize continuous R&D-compelled learning and encourage interdepartmental collaboration to enhance diffusion of innovation and operational quality. Furthermore, policymakers such as the Federal Ministry of Industry, Trade and Investment and NITDA ought to provide incentives to companies that invest in R&D-driven managerial development. The study contributes to the growing body of literature on strategic innovation management by underlining the role of R&D activities in facilitating managers to balance creativity and administrative order successfully in realizing organisational goals.