Provided are a wafer level package and a method of manufacturing the same, wherein an underfill sufficiently fills a space between a redistribution substrate and a semiconductor chip, thereby reducing warpage. The wafer level package includes a redistribution substrate including at least one redistribution layer (RDL), a semiconductor chip on the redistribution substrate, and an underfill filling a space between the redistribution substrate and the semiconductor chip. The underfill covers side surfaces of the semiconductor chip. The redistribution substrate includes a trench having a line shape and extending in a first direction along a first side surface of the semiconductor chip.