The present invention provides polymorphic form of regadenoson and its acid addition salts selected from the group comprising of regadenoson hydrochloride, regadenoson hydrobromide, regadenoson maleate, regadenoson fumarate, regadenoson succinate, regadenoson sulfate, regadenoson acetate, regadenoson mesylate, regadenoson tartrate or regadenoson* lactate.