The aim of this research work was to Evaluation of Some Natural Polymer used as Sustained Release Matrix Tablet, any pharmaceutical formulation contains two ingredients one is the active ingredient losartan Potasium and other is an excipients. In current senario, various plant have been studied for their diverse applications as excipients like binders, granulating agents, disintegrants, emulsifiers, suspending agents, gelling agents, mucoadhesive agents, matrix-formers, release retardants, enteric resistants, etc., in various pharmaceutical dosage forms. Among these, tamarind seed polysaccharide & okra mucilage is an emerging excipient, which is being used and investigated for the preparation of various dosage forms like suspensions, emulsions, tablets, gels, creams, etc. The current chapter deals with a comprehensive and useful discussion on extraction & isolation, chemical composition and properties of tamarind seed polysaccharide & okra mucilage. In the tablet, Extended Release layer consist of Antihypertensive Drug belonging to class β-selective adrenergic blocking agent without partial agonist or membrane stabilizing properties. Extended release preparation provides sustained release and reduces the chances of tough related side effects. In selected cases of extended release preparation of this drug used in treatment of hypertension and congestive heart failure. The clinical studies have shown beneficial role of this drug as an extended release preparation. An excipients help in the manufacturing of dosage form and it also improves physicochemical parameters of the dosage form The main objective of the present study was to develop, formulate and evaluate a matrix tablet by using hydrophilic natural retardant polymers which would retard drug release in upper GI tract and should start releasing the drug when it reaches the alkaline environment of small intestine. Okara and Tramarind Gum Mucilage were investigated as the model hydrophilic retardant polymers. Nine batches of tablets were prepared. The prepared tablets were subjected for pharmacopoeial and non-pharmacopoeial evaluation parameters including loose and tapped bulk density, compressibility index, hausner ratio, angle of repose, friability, hardness, thickness, weight variation, % drug content and in-vitro drug release studies. It can be concluded that the combination of hydrophilic polymers that are retardant in nature are better suited for sustained and controlled drug delivery system than the hydrophilic polymer alone. Key Words: Polymer, Sustained Release, Tablet, Drug, Extraction.