Terahertz (THz) radiation possesses unique characteristics that offer enormous application value in frontier scientific research fields, including the high-sensitivity analysis of biomacromolecular structures and various other areas. For advanced spectrometers such as Dynamic Nuclear Polarization Enhanced Nuclear Magnetic Resonance (DNP-NMR) and Electron Spin Resonance (ESR), increasing the power and frequency of THz wave sources is crucial for enhancing the resolution and signal-to-noise ratio of the instruments. However, traditional slow-wave devices and quantum cascade lasers encounter significant challenges when transitioning to the THz frequency range, which often limits their THz power to typically less than ten watts. Fast wave devices, such as gyrotrons based on the Electron Cyclotron Maser (ECM), provide significant advantages in terms of high frequency and power. These devices leverage the efficient interaction between gyrating electrons and fast waves within a resonant cavity, facilitating the generation of high-power radiation in the THz frequency range, with output levels reaching up to megawatt level. However, gyrotrons operating in the THz frequency range require high magnetic field strengths, e.g. approximately 37T is required for 1THz, which exceeds the capability of existing commercial superconducting magnets (usually below 20T). To increase the output frequency of the gyrotron, it is essential to employ high-harmonic operation or pulsed high magnetic field techniques. The Wuhan National High Magnetic Field Center (WHMFC) has developed an 800 GHz second harmonic gyrotron. An experimental research platform has been established, including a 15T superconducting magnet, power supply system, and THz wave measurement system. Experimental results indicate that the stable oscillation of TE_8,5 second harmonic operating mode can be achieved, with a frequency around 799.6 GHz and a maximal power output of 150W^[1]. This gyrotron can satisfies the demands for high-power THz wave sources required for applications such as DNP-NMR and ESR. Currently, a 1THz gyrotron based on a flat-top pulsed magnetic field with duration of 10ms is under development. A 40T long-pulsed magnet has been designed, manufactured and tested successfully^[2]. The 1THz gyrotron tube has been design and fabricated and is under test. In the near future, a series of gyrotrons operating at 140GHz, 400GHz, and other frequencies will be developed to be applied in DNP-NMR and ESR spectrometers for scientific research on the structural analysis of biomacromolecules.