In recent years, the Simultaneous Magnetic Actuation and Localization (SMAL) technology has been developed to accelerate and locate the wireless capsule endoscopy (WCE) in the intestine. In this paper, we propose a novel approach to detect the state of the capsule for improving the localization results. By creating a function to fit the relationship between the theoretical values of the actuating magnetic field and the measurement results, we present an algorithm for automatic estimation of the capsule state according to the fitting parameters. Experiment results on phantoms demonstrate the feasibility of the proposed method for detecting different states of the capsule during magnetic actuation.