Abstract: This paper deals with the method of oscillopolarographic titration of hyos- cine butylbromide (injections and tablets) with Na-tetraphenylborate (Na-TPB) solution. An excess amount of standard solution of Na-tetraphenylborate is added to an acetate buffer solution ( pH=5.1—5.3 ) containing the sample to precipitate hyoscine butylbromide quantitatively. Filter through a dry filter, transfer a measured volume of the filtrate to a beaker, adjust the solution to alkaline and titrate the excess Na- tetraphenylborate with standard thallous sulfate solution. This method is found to be accurate and rapid. The excipient and additive used did not interfere with the determination.