A novel angiography system with cone-beam reconstruction using a large-area flat panel detector (FPD), with 40x30cm active area and 2048x1536 matrixes with a 194μm pixel pitch, has been developed. We present results on a basic performance, spatial resolution and contrast detectability obtained on this angiography system with cone-beam function using the FPD, and compare with a conventional angiography system with an image intensifier (I.I.) and charge-coupled device (CCD) camera. We’d achieved a fast acquisition, 15 seconds as for a subtraction mode by rotating a ceiling suspended C-arm at a speed of 40 degrees per second, and ensured a large reconstructed columnar volume, φ250mmx180mm, by using the large-area detector. As a result of the evaluation, the 3D image acquired from the FPD system has a high spatial resolution with no distortion and good contrast detectability.