Floating Drug Delivery Systems have emerged as an efficient means of enhancing the bioavailability and controlled delivery of Diltiazem hydrochloride. Drug absorption in the gastrointestinal tract is a highly variable processes and prolonging the gastric retention of dosage form via floating drug delivery system extends the time for drug absorption and ultimately increase bioavailability of drug. Diltiazem hydrochloride is a benzothiazepine-derivative calcium-channel blocker was chosen as a model drug due to its low oral bioavailability (30-40 %), short half-life (3 to 4 hrs), High frequency of dosing and low solubility at lower part of GI tract which makes it an appropriate candidate for a formulation in a sustained release floating drug delivery system, twice-a-day dosage form. The present study was aimed at designing a effervescent floating tablet of Diltiazem hydrochloride for controlled release of Diltiazem using different grades of Hydroxy propyl methyl cellulose such as HPMC K4M, HPMC K15M, HPMC K100M and Xanthan gum to achieve improved economy of tablet. Sodium bicarbonate and citric acid was used as a gas generating agent.