PURPOSE: To obtain the PLL oscillator in which noise attended with frequency division is reduced and the radio equipment provided with the PLL oscillator.

CONSTITUTION: When a disconnection means 7 disconnects a phase locked loop, a voltage holding circuit 8 holds a control voltage fed to a voltage controlled oscillator 1 to a value just before the disconnection during loop disconnection. Thus, the voltage controlled oscillator 1 keeps the output of the oscillating frequency just before the disconnection of the phase lock loop even during the disconnection of the phase locked loop and since the phase locked loop is disconnected for the time, no noise attended with frequency division is included in the output of the voltage controlled oscillator 1. Thus, when the forming/ disconnection of the loop is repeated in this way, the noise quantity attended with frequency division included in the output of a PLL oscillator controlling the voltage controlled oscillator 1 is totally reduced. Furthermore, the PLL oscillator is employed for a reception section and a transmission section of the radio equipment while part of the oscillator is in use in common.