In this study, adsorption of Cu and Zn onto Ficus Religiosa has been investigated. Experimental data have been studied by  Five two-parameter models (Langmuir, Freundlich, Stephan Brunauer, Paul Emmett, and Edward Teller (BET), Temkin, Dubinin–Radushkevich), Five three-parameters (Redlich–Peterson, Sips,  Toth ,Koble-Corrigan, Radke-Prausnitz) and four kinetic models (Pseudo first order, pseudo second order, the Elovich Kinetic and Weber Morris (Interaparticle diffusion) Kinetic Model. In this study, six non linear error functions (Coefficient of Determination, Sum Squares Errors, Mean Square Error, Root Mean Square Error, Sum of the Absolute Error, Average Relative Error) were examined in order to identify the best adsorption isotherm and kinetic models for Cu and Zn adsorption on Ficus Religiosa. From the results it is concluded from the results that three parameters isotherms shows the better fit of the given experimental data as compared to the two parameter isotherms.  Among two parameter isotherms, the linear and non-linear forms of Temkin adsorption equilibrium isotherm best fit the given experimental data for Cu & Zn metals adsorption onto Ficus Religiosa. It confirms the formation of unimolecular layer of Cu and Zn by Ficus Religiosa.  Apart from three parameter isotherms, the linear and non-linear mathematical forms of Redlich–Peterson adsorption equilibrium isotherm best fit the experimental data for Cu metal adsorption with the closest value of coefficient of correlation to unity. On the other hand, the linear and non-linear forms of Sips adsorption equilibrium isotherm shows the closest fit of the experimental data of Zn adsorption by Ficus Religiosa. Experimental data shows that maximum adsorption capacity of Ficus Religiosa is 28.03 mg/g and 24.89 mg/g for Cu and Zn adsorption respectively. On the other hand, among four adsorption kinetic models, the Pseudo second order kinetic model best fit the given experimental data for Cu and Zn adsorption.