There are several factors that have influence on the phase noise of an oscillator. But one of the major factors is the flicker noise of a transistor, since the phase noise of an oscillator is generated by mixing the carrier with the low frequency noise near the DC having the characteristic of 1/f. In this paper, we have presented a method on reducing the phase noise of an oscillator by using a low-frequency feedback circuit based on an active bias circuit, and have fabricated a DRO for a DBS receiver. Measurement results show that the phase noise is -92 dBc/Hz at the 10 KHz offset frequency, and from these results we have found out that the reduction method is very effective.