Bacterial cellulose (BC), produced by Acetobacter xylinum, has been given a great attention due to its high potency for many industrial applications. An optimized substrate is important for higher BC production; thus, an alternative natural product, as a carbon source, should be determined. This study aims at investigating the BC of A. xylinum cultured in coconut water and pineapple juice-based media and to predict its fermentation kinetics. The BC was produced on two stages of fermentation system, the shaking culture for propagation and the static culture fermentation for BC production. A. xylinum exhibited exponential phase at 48 h which showed BC production associated with its cell growth on both substrates. Fermentation kinetics of A. xylinum using coconut water and pineapple juice revealed Rp 0.117 and 0.051 g/l/h, Rx 0.309 and 0.133 g/l/h, Rs 0.079 and 0.215 g/l/h, Yx/s 1.408 and 0.240 g biomass/g glucose, Yp/s 3.612 and 0.599 g cellulose/g glucose, Yp/x 2.235 and 2.452 g cellulose/g biomass, µmax 0.0132 and 0.0082/h, σ 0.028 and 0.0173/h, respectively. Overall parameters of fermentation kinetics revealed a high rate of BC formation and efficient conversions of glucose to biomass and BC by A. xylinum on coconut water substrate. Thus, coconut water proved to be a more suitable substrate to produce BC in comparison with pineapple juice.