Biosorption of bromothymol blue from wastewater using biocomposite developed from Gliricidia sepium (A) and Acacia pods (B) was studied. The biocomposite were developed based on the Mixture Methodology of the to Design Expert software (11.0.4), where the mixed ratio was varied from 5 to 95 percentage composition and the effective mixture was evaluated based on methylene blue number (MBN) test. Adsorption capacity (AC) and Removal efficiency (RE) of the seven (7) experimental runs was studied. The surface characteristics of the materials were chemically modified and characterized using Fourier Transmission Infrared (FTIR). Batch adsorption was carried out at 10 mg/l, 15 mg/l and 20 mg/l initial concentrations at various contact time. Suitable adsorption Isotherms, kinetics models, mass transfer diffusion models and thermodynamics were studied. The RE (%) and AC (mg/g) have the highest values (96.9736 and 0.969736) at Run 3 (0.95A: 0.05B). There were appearance and disappearance of the O-H stretch, C=O, C-F, c≡c, ≡C-H stretch groups in the modified and unmodified Gliricidia sepium at different peaks, while C-Cl stretch, C=O, N-H bend and O-H stretch groups were noticed in the modified and unmodified Acacia pod. The Temkin and Freundlich Isotherm represented the best fit of experimental data. The kinetic studies revealed that the pseudo-second order model fitted well. The mechanism of adsorption was controlled by Weber-Morris diffusion model. The activation thermodynamic parameters were estimated. Results showed that low-cost adsorbents can be fruitfully used for the removal of dyes with a concentration range of 10-20 mg/l, it also showed that Gliricidia sepium and Acacia pod biocomposite was effective in removal of bromothymol blue from wastewater.