A carbon steel sheet having high formability due to a microscopic and uniform carbide distribution and having a good characteristic of final heat treatment, and a manufacturing method thereof. The carbon steel sheet having excellent formability includes, in wt %, C at 0.2-0.5%, Mn at 0.1-1.2%, Si at less than or equal to 0.4%, Cr at less than or equal to 0.5%, Al at 0.01-0.1%, S at less than or equal to 0.012%, Ti at less than or equal to 0.5×48/14×[N]% to 0.03% when the condition of B and N is not satisfied, B at 0.0005-0.0080%, N at less than or equal to 0.006%, Fe, and extra inevitable elements; an average size of carbide is less than or equal to 1 μm; and an average grain size of ferrite is less than or equal to 5 μm.