Abstract: High power divider with ultra-wide-band was designed based on coaxial structure. The divider input impedance was first translated to the desired impedance for matching and then the offset was made to ease the mechanical processing. High frequency simulation software was used to simulate the divider and the practical divider was fabricated. High voltage experiment shows that the divider can resist high power up to millions watt. The measurement of voltage standing wave ratio(VSWR) is less than 1.5 from 0.18 GHz to 0.85 GHz and the average value is about 1.2. The transmission parameters indicate the output ports have well amplitude consistency. The measurements show that the divider is applicable to high power antenna array.