A fault signal recovery apparatus and method for collecting signals obtained in a plant and recovering normal signals from fault signals contained in the measured signals through a machine learning method includes receiving an input X including only normal signals for a plurality of tags, an input U including fault signals for a first group of tags among the plurality of tags and normal signals for a second group of tags, and an input S having information on the first group of tags including fault signals, and estimating and recovering normal signals for the first group of tags including fault signals based on feature information F, recovery model information P, and ensemble learning.
