Two new simplified quantitative detection methods for misalignment faults are proposed based on the eddy current sensor. A simplified series method based on Fourier series to estimate amplitude and phase is introduced to obtain the amounts of parallel and angular misalignment. Another method based on two points measurement is also proposed to achieve more rapid estimation of misalignment. The principles of measurement and calculation of the two methods are explained, and their performance and effectiveness are verified by simulation and experiments. Experimental results show that the simplified series method can quantitatively detect the misalignment faults of rotating machinery, and the two points measurement method has great practical significance in the rapid estimation of misalignment.