Abstract: A 2.5 GW long pulse power module with impedance of 6 Ω is developed for repetitive pulse LTD generator. In order to increase output power, optimize configuration and improve waveform aberration, four annular Blumlein PFNs driven by two switches synchronously are designed, and high voltage pulse can symmetrically feed primary coil of a linear transformer in four directions. There are performed experiments of adding voltage in two 2.5 GW LTD modules, and this equipment can produce pulses with power of 5.2 GW, half width of 160 ns and repeat rate of 5 Hz in virtue of laser trigger spark switches technology.