Many scholars emphasized that employee team effectiveness affects organizational performance. However, empirical evidence related to the team effectiveness of executive-level employees and organizational performance in the Sri Lankan apparel industry represents a significant gap in the literature. Therefore, the study was carried out to explore the impact of team effectiveness on organizational performance in the Sri Lankan apparel industry. From the critical review of literature, contextual factors, team composition factors, and team process factors were identified as the independent variable of the study. While organizational performance was identified as the dependent variable. This study was based on primary data collected from 181 executive-level employees who work for large-scale apparel companies in the North Western province. Data collected through a structured questionnaire and analysed using linear regression analysis. The results of the study reveal that the team effectiveness of the executive level employees has a significant impact on organizational performance. Team process factors are deemed to be the most influential component of the team effectiveness while contextual factor is the least influential team effectiveness factor. All the independent variables were positively correlated with organizational performance. With the findings of the study, policymakers and the management of the companies are able to formulate the relevant strategies to get the maximum output from the team effectiveness of the executive level employees to increase the overall organizational performance in the Sri Lankan apparel industry.