An isolated chimeric peptide consisting of one or two added peptides and an object peptide wherein the added peptide is bonded to the N-terminus, the C-terminus or both of the object peptide, wherein if the added peptides are bound to both terminals, the two added peptides may be the same or different; and physiological activity of the object peptide is still retained, wherein the object peptide is a natural physiologically active peptide selected from the group consisting of an atrial natriuretic peptide, a brain natriuretic peptide, a C-type natriuretic peptide, motilin, a glucagon-like peptide 1, parathyroid hormone, and calcitonin, or a derivative of any thereof, wherein the derivative has one or more amino acid(s) deleted from the amino acid sequence of a natural physiologically active peptide and has the desired physiological activity.