An approach for the enzyme-mediated in-situ synthesis of polymers in two dimensions on a Langmuir trough surface is reported. Horseradish peroxidase-mediated polymerization of monomer mixtures of unsubstituted and long alkyl chain substituted phenols and aromatic amines at the air-water interface was demonstrated. The use of the Langmuir trough to organize and orient the reactants results in improved control of monomer reactivity and orientation in the resulting polymer compared to the polymer synthesized in bulk solvent. In turn, this enhanced control results in improved processability because of reduced chain branching. Good thermal stability and significant electronic and optical properties of the ordered polymer were demonstrated. This interfacial polymerization procedure creates opportunities in the development of improved materials for applications in biology, medicine, and microelectronics.