To provide a digitally controlled oscillation device and a high frequency signal processing device that reduce noise remote from an oscillation frequency.

A plurality of unit capacitance units CIU[1]-CIU[k] are, for example, used to implement a fractional capacitance. In CIU[1], capacitive elements CFXp[1], CFXm[1] have ends on one hand connected to oscillation output nodes OscP, OscM, respectively. Meanwhile in CIU[2]-CIU[k], capacitive elements CFXp([2]-[k]), CFXm([2]-[k]) have ends on one hand connected to a fixed voltage V6. In CIU[1]-CIU[k], the capacitive elements on one side have the other ends connected in common (SWFD), and the capacitive elements on the other side have the other ends also connected in common (SWFS). Switches (SWF1-SWF3) in CIU[1]-CIU[k] are turned on/off by common control.