The invention relates to an unbalanced azimuth estimation method based on a holo-spectrum technology, which is characterized by comprising the following steps: 1) determining a phase position of an initial phase point, installing two sensors which are perpendicular to each other on a measuring section, describing vibration response by a holo-spectrum mode based on information infusion to completely reflect vibration behavior of a rotor, and determining the phase position of the initial phase point after information fusion; 2) taking the phase position of the initial phase point after information fusion as a vibration high-point phase position, and defining a mechanical lag angle with an angle showing that an unbalanced vibration response phase position expressed by initial phase point azimuth falls behind an unbalanced excitation force; and 3) estimating unbalanced azimuth by means of the mechanical lag angle based on the phase position of the initial phase point. On the basis of a holographic principle, in term of the key problem of unbalanced azimuth estimation, the method of the invention adopts the initial phase point instead of a vibration high point in the traditional estimation method using a single sensor, and transforms the traditional mechanical lag angle method by combining starter-stopper data, thus effectively improving unbalanced estimation accuracy and being an effective means for realizing the one-time addition method.