Cotton linter (CL) is a by-product of the garment industry that is good raw material forrncellulose preparation. The aim of this study was to extract and characterize native cellulosernand cellulose acetate (CA) from CL and evaluates CA as a sustained release excipient inrntablet formulation. In this study, cellulose was extracted by steam explosion method and CArnwas prepared from the extracted cellulose by using acetic anhydride as acetylating agent andrnsulphuric acid as a catalyst. Physico-chemical properties of cellulose and CA wererncharacterized. Mechanical properties of plain CA tablets and release profile of theophyllinernas a model drug were investigated from CA matrix. The cellulose yield from CL on dryrnweight basis was found to be 78.06%+1.70, while CA yield from cotton linter cellulosern(CLC) was 112.4%+1.28. The degree of polymerization (DP) of CLC was 472.52+3.64,rnwhile DP of cotton linter cellulose acetate (CLCA) preparations ranged from 148.24+1.80 -rn234.09+4.12 based on their degree of substitution (DS). The identification of CLCA wasrnconfirmed by Fourier transform infrared (FTIR) spectra, while CLC was identified by usingrnchemical test in addition to FTIR. The degree of crystallinity of CLC was 81.59% and thosernof CLCA with DS 0.83 and DS 2.46 were 57.92% and 33.78%, respectively. Scanningrnelectron microscopy (SEM) of CLC showed fibrous morphology while SEM of CLCArnrevealed aggregated particles. The CLCA with DS 2.46 exhibited better heat stability thanrnCLC and comparable result with commercial cellulose acetate (CCA). However, CLCrnexhibited better thermal stability than CLCA having DS 0.83. The CLCA with DS 2.46rnexhibited good flow properties making it suitable for direct compression. The release studyrnshowed that, matrix tablets of CLCA with DS 2.46 preparations exhibited prolongedrndisintegration times and retarded in-vitro dissolution than tablets prepared with CLCA DSrn0.83 and comparable result with CCA. However, CLCA had higher % release of drug asrncompared to ethyl cellulose (EC) containing formulation. The drug release rate was alsornprolonged as the percentage of CLCA DS 2.46 increased from 59.5% to 79.5% (w/w). Thernkinetic study showed that, the formulations are best fitted to the Higuchiâ€Ÿs square root kineticrnmodel (Rrn2rn = 0.9862 to 0.9976) indicating the release of drug from the matrix was diffusionrnbased. Therefore, CL could be a potential local source of cellulose while CLCA could be arnpotential candidate as a sustained release excipient.