Abstract: A method and disc reading device for detecting an unbalanced disc are disclosed. The disc reading device includes a first sensor, a second sensor, a cache memory, an operating unit and a data table. The first sensor and the second sensor respectively detect a first parameter and a second parameter when the disc reading apparatus driving the disc at a predetermined voltage. When the first parameter is detected as being equal to a first predetermined value, the cache memory records the second parameter as a first corresponding value. When the second parameter is detected as being equal to a second predetermined value, the cache memory records the second parameter as a second corresponding value. The operating unit calculates a difference between the first and the second corresponding values to obtain the unbalance status.