The stretch bending limit, fracture location and fracture morphology of 800  MPa dual phase (DP) steel sheets under different punch radii was determined through series of U-shape stretching bending tests. The limit bending test was numerically simulated and three yielding models: Hill, Barlat and BBC were compared in the numerical simulation. For those tests with bigger punch radii (Rp≥2.5 mm), the fracture of limit bending can be predicted using the Hill yielding model, using the traditional forming limit curve (FLC) as fracture criterion. However, the fracture of limit bending can’t be predicted using the same criterion with smaller punch radius (Rp=1.0 mm); the reason is that the necking based traditional FLC neglects the bending effect with smaller punch radii while the bending of 800 MPa DP steel sheets under this condition shows no obvious necking shear fracture, the actual fracture limit is lower than the traditional FLC.