Abstract: A substrate for measurement of .alpha.-amylase activity comprising a malto-oligo saccharide respresented by general formula (I) or (V) described below:A--Gn--B (I)A--Gn--I (V)wherein A represents: ##STR1## B represents a monosaccharide or a derivative thereof other than glucose; I represents inositol or a derivative thereof; G represents glucose; and n represents an integer of 3 to 15; in formula (II) or (III), R.sub.1 to R.sub.4 each represents a hydrogen atom, a lower alkyl group or (CH.sub.2)yCOOM (wherein y is 0, 1 or 2 and M represents a hydrogen atom or an alkali metal); and X.sub.1 to X.sub.4 each represents an oxygen atom or a sulfur atom.