The present inventive concept relates to a battery-free gas sensor or humidity sensor comprising a metal-organic framework and a method of manufacturing the same. In a photodiode-type battery-free gas sensor or humidity sensor according to the present inventive concept, since photoelectron collection electrodes are formed at certain intervals between P-N junction layers, when gas is adsorbed thereon, the gas can be detected without an extra power source by change of photocurrent. Due to fine pores of the metal-organic framework, gas sensitivity may be increased and stability of catalysts may be improved. When catalysts are not provided, humidity may be detected. Therefore, a system that used the photodiode-type battery-free gas sensor and the photodiode-type battery-free humidity sensor together may be performed humidity correction to accurately measure an amount of a gas.