Abstract: A novel digital tuning wideband oscillator with the function of frequency agility is presented in this paper. Its agile time is less than 1μs. Firstly,the basic principle of digital tuning oscillator is given,and then a nonlinear compensation method of tuning voltage in the design of voltage-controlled oscillator (VCO) is discussed. The study of this paper focuses on analyzing the factors affecting the frequency agile ability of digital tuner oscillator and looking for a good method of reducing frequency agile time. Finally,the relationship between the frequency agile time and compensated capacitor of operational amplifier is measured and analyzed. The digital tuning oscillator frequency accuracy is ±2MHz,and the phase noise is -75dBc/ Hz@100kHz.