Disclosed is a recombinant microorganism capable of growing using only carbon dioxide and formic acid by introducing and improving a metabolic pathway for synthesizing pyruvic acid from carbon dioxide and formic acid to enhance pyruvic acid synthesis efficiency and performing additional genetic manipulation, and a method for producing useful substances using the same. Advantageously, the recombinant microorganism is capable of synthesizing pyruvic acid, a C3 organic compound, at a remarkably improved rate, and in particular, grows well even in a medium containing only carbon dioxide and formic acid as carbon sources without a glucose supply, and is thereby capable of synthesizing pyruvic acid and various high value-added compounds using the same as an intermediate product in an economically efficient manner.