A method of manufacturing a redistribution circuit structure and a method of manufacturing an INFO package at least include the following steps. An inter-dielectric layer is formed over a substrate. A seed layer is formed over the inter-dielectric layer. A plurality of conductive patterns are formed over the seed layer. The seed layer and the conductive patterns include a same material. While maintain a substantially uniform pitch width in the conductive pattern, the seed layer exposed by the conductive patterns is selectively removed through a dry etch process to form a plurality of seed layer patterns. The conductive patterns and the seed layer patterns form a plurality of redistribution conductive patterns.