The research on the enzymatic reaction in a batch emulsion liquid membrane process was carried out in two aspects. First, a mathematical model was developed for analyzing the rate and conversion of reaction using an enzyme encapsulated by stable water-in-oil (W/O) emulsion. Second, the influence of emulsion preparation variables on the reaction conversion and membrane stability was investigated for optimizing the practical process. The proposed mechanism of model is bases on the simple-diffusion (type 1) facilitation of the permeation-consumption of substrate and the carriermediated (type 2) facilitation of the generation-permeation of product. Input to the model is the phase and chemical equilibria at the interface of external-emulsion and internal-membrane phase. The developed model takes into account the reactivity of internal enzyme, intra-emulsion diffusion and peri-emulsion mass transfer for both substrate and product. Parametric study showed that several parameters have significant influence on the enzymatic reaction with emulsion liquid membrane. The parameters affecting the substrate consumption are Thiele modulus, Biot number, and the relative emulsion capacity to the external phase. The parameters influencing the product generation are carrying capacity and pumping parameter. The proposed model was applied to the hydrolysis of L-phenylalanine methyl ester into L-phenylalanine by and emulsion liquid membrane containing $\alpha$-chymotrypsin in the internal phase. All parameters needed for modeling could be estimated without using adjustable parameters, but only the thermodynamic, transport, emulsion and enzyme properties. The model predicts satisfactorily the experimental results of the enzymatic reaction in a batch system under various conditions. The effects of W/O emulsion preparation variables on the membrane stability, as well as the transport rate of substrate and product, were studied in a same batch EELM process as that in model application. T...