Metriochroa syringae is a moth of the Gracillariidae family. It is known from Hokkaido island in Japan. The wingspan is 5.6-6.5 mm. The larvae feed on Syringa reticulata. They mine the leaves of their host plant. The mine starts as a narrowly linear mine. Later, it gradually widens into a very long and irregularly curved gallery that is sometimes fused into a large blotch. The last sap-feeding larva makes an inter parenchymal mine, so that the mine is seen from the upper side of the leaf as a trace of pale greenish mottles in this stage. A pupal chamber is found within the mine, but not always at the end of the mine. It is ellipsoidal, with very slightly swollen upper and lower sides.