The stagnant nature of Sri Lankan national coconut production over many decades has been an issue in fulfilling the ever-increasing demand for domestic coconut consumption and industry. Thus, this study aims to address the question of the driving forces of total coconut production growth. This study identifies the sources of Sri Lankan coconut sector growth from 1985 to 2019 by calculating the Total Factor Productivity (TFP) growth by administering a log-transformed Cobb–Douglas production function and decomposed the results using a data set sourced from various government publications. According to the findings of the study, the average TFP growth of the coconut sector in Sri Lanka for the period 1985-to 2019 has been -1.1%, whereas it was -0.1% and -1.9% during the two sub-periods; 1985-2000 Sub-period I, 2001-2019 Sub-period II, respectively. Therefore, it is evident that the negative growth of the TFP is mostly driven by the high negative growth in the post -2000 period. These findings will help to formulate future growth policies in coconut sector of Sri Lanka.