The intensity of integrating green intellectual capital into business strategies and policies to address sustainability concerns rises sharply. However, limited research exists on how information technology capabilities can improve the impact of green intellectual capital on sustainability in service sectors of developing countries like Bangladesh. This research addresses this research gap by exploring how human, relational, and structural dimensions of green intellectual capital contribute to gaining business sustainability in the service sector. Furthermore, it also observes how information technology capabilities can further strengthen these effects. The study employs a quantitative approach where a survey was conducted with 465 personnel from the service sector in Bangladesh using online platforms. Structural Equation Modeling was employed with AMOS software to analyze the data. The results reveal that green human capital, rational capital, and structural capital significantly enhance business sustainability. And, the results also evident that information technology capabilities were found positive to foster green intellectual capital on sustainability, indicating the value of technological integration in sustainability practices. The study leaves a message to policymakers, managers, and researchers that, strategic investing in green intellectual resources and technological capabilities is critical to promoting sustainable business practices, especially in the service sector.