The present study was focused on preparation and evaluation of SR pellets of Bosentan. The preparation of extended release (ER), drug pellets of Bosentan were prepared by using fluid bed coating (FBC). These drug-loaded pellets were further coated with ethyl cellulose of two viscosity grades and Eudragit as rate controlling polymers, hypromellose as pore former and binder, acetyl tributyl citrate as plasticizer, and magnesium stearate as anti-adhering agent. The prepared pellets were evaluated for drug content, invitro dissolution, DSC, FTIR and SEM. The prepared pellets were subjected for accelerated stability study. The drug release was extended up to 24 hours and the dreg release was mainly depends on the polymer type and polymer proportion. Accelerated stability showed good similarity with the initial formulation indicated good stability for 6 months. DSC and FTIR study showed the no drug polymer interaction. This technique can be showed good commercial success.