The influence of Multi Walled Carbon Nano Tube (MWCNT) in oxygen cross over, water absorption and performance of chitosan (CHIT) in Single Chamber Microbial Fuel Cell (SCMFC) was studied. CHIT and non covalently functionalized MWCNT with CHIT (CHIT-MWCNT) were prepared in the form of membranes and characterized using FTIR, XRD, DRS UV, CD, Raman, SEM and TEM to study the interaction of MWCNT with chitosan. CHIT-MWCNT showed lesser water absorption compared to that of CHIT. CHIT-MWCNT membrane showed oxygen mass transfer coefficient (2.66 x 10(-4) cm/s) one order less than that of CHIT (2.28 x 10(-3) cm/s). The prepared membranes were continuously tested in an in-house built Single Chamber Microbial Fuel Cell (SCMFC). The maximum power density obtained by CHIT-MWCNT composite membrane was higher compared to that of CHIT membrane obtained was 38.16 mW/m(2) and 46.94 mW/m(2) for CHIT and CHIT-MWCNT, respectively. The results of the study showed that the MWCNT incorporated chitosan composite membrane had strong influence on the properties and performance of CHIT in microbial fuel cell. Hence, CHIT-MWCNT is a promising candidate for application in microbial fuel cell. (c) 2013 Elsevier B.V. All rights reserved.