This study was conducted to determine the profitability of betel leaf production in Bangladesh from the view point of different aged Boroj, i.e. new Boroj (1 to 5 years), mid-aged Boroj (6 to 15 years) and old Boroj (above 15 years). Three villages namely Maria, Chaubania and Raipara of Maria. union from Rajshahi district were selected purposively for the study and in total of 120 betel leaf growers were selected as samples by using stratified random sampling technique of which each stratum consisted of 40 betel leaf growers. Primary data were collected from the selected betel leaf growers during the period of January to June 2001. A simple cost and returns analysis was done to determine the profitability of betel leaf production. Further, Cobb-Douglas production function was used to determine the contributions of key inputs to betel leaf production using seven explanatory variables in the model. The annual costs of production of betel leaf per hectare were estimated at Tk. 2,67,260.40, 1,95,879.04 and Tk. 2,06,914.13 for new mid-aged and old Boroj, respectively and corresponding net returns per hectare were Tk. 4,25,625.28, 2,84,670.18 and Tk. 2,58,857.54, respectively The study revealed that betel leaf production was a profitable business. Further, betel leaf production in new Boroj was more profitable than those in mid-aged and old Boroj. Also the estimated R2 and F-value confirm significant use of inputs on betel leaf production and showed increasing returns to scale.