PROBLEM TO BE SOLVED: To provide a plant bright and insect pest-controlling composition capable of exhibiting a high effect to the vegetable blight and insect pest at an actual controlling place even if having a low amount of an active ingredient, and a method for controlling the vegetable blight and insect pest by using such the composition.SOLUTION: This vegetable blight and insect pest-controlling composition is characterized by containing (a) ≥1 kind of quinoline compounds expressed by general formula (I) [wherein, R1 to R4 are each alkyl, a halogen atom or the like； X, Y are each a halogen atom or the like； (n) is an integer of 0 to 4: and (m) is an integer of 0 to 6] or their salts and (b) a specific known insecticidal, acaricidal and nematicidal compound (eg. dinotefuran) as the active ingredients.
