A flexible, wideband, and screen-printed antenna is proposed. The antenna is coplanar-waveguide (CPW) and composed of two inverted L-shape elements, a matching stub, and a defected ground structure (DGS), with a total area of 55 40 0.125 mm3. Studies show that the DGS can significantly increase the antenna bandwidth from 30% to 119% without sacrificing the size. The antenna has a wide measured bandwidth of 1.77 - 6.95 GHz, and a measured peak gain and efficiency in the ranges of 2.5-5.9 dBi and 60%-90%, respectively. Furthermore, both simulation and measurement confirm that the performance of the antenna is relatively stable under the bending conditions with various curvature radii.