Garments and textiles exports play a significant role in the Sri Lankan economy. This study focused to model and forecast garments and textiles exports in Sri Lanka from 2009 to 2018. USA, UK, Italy, Germany and Belgium are main markets of garments and textiles exports in Sri Lanka. Monthly garments and textiles exports data were collected from Sri Lanka Customs. Values generated from garments and textiles exports show upward trend with seasonal fluctuations throughout the period. Seasonal indexes were developed to capture seasonal fluctuations. In this study, Box-Jenkins methods were used to build time series models. Seasonal auto regressive moving average (SARIMA) model was best fitted for total garments and textiles exports values. The best model was selected according to Akaike criterion, Schwarz Criterion and Hannan-Quinn Criterion. Model was validated by mean squared error (MSE). According to the model selection criteria SARIMA (2, 1, 0) (1, 0, 2)¹² was identified as the best fitted model for total garments and textiles exports of Sri Lanka.