A localization and attitude estimation method using magnetic fields includes the following steps. First, in three-dimensional coordinates, at least three magnetic landmarks arbitrarily disposed around a moving carrier are selected, wherein any two of the at least three magnetic landmarks have different magnetic directions. One set of at least five tri-axes magnetic sensors is used to sense the magnetic fields of the at least three magnetic landmarks. Three magnetic components on three axes of a current position of each of the tri-axes magnetic sensors are respectively generated by a demagnetization method. Five non-linear magnetic equations are solved to obtain position information and magnetic moment information of the at least three magnetic landmarks in the three-dimensional coordinates. Position vectors and attitude vectors of the set of at least five tri-axes magnetic sensors in a three-dimensional space are estimated based on tri-axes magnetic moment vectors of the magnetic landmarks.