In wastewater treatment microbial cultures immobilised on various matrices are used to protect the microbes from confronting shock loads of organic pollutants. Because of the beneficial effect of activated carbon, it is generally used as a carrier material in comparison to other matrices. In this study mutant strain of P. pictorum (MU 174) was immobilised on ricebran based activated carbon. The effect of contact time, pH, particle size, mass of activated carbon, temperature and ionic strength on adsorption of MU 174 on activated carbon were investigated. The adsorption kinetic parameters like K _p , K _ad and H were also determined.