Abstract: For the endoscope with imaging fiber bundle, either the configuration or the imaging quality of its objective lens should satisfy some new requirements. Firstly, the fundamental of the objective lens design was analyzed, and the retrofocus objective lens was chosen as an initial structure for this design. Then an objective lens for the fiber-optic endoscope was designed with the software Zemax. The operation wavelength, focal length, FOV(field of view) and relative aperture of the designed lens are 0.38-0.78 m, 0.921 mm, 100 and 1/4 respectively. Its total length is 10.32 mm. It's telecentric in image space. The MTF value of the lens is greater than 0.85 at the spatial frequency of 38 lp/mm. Furthermore, a model of the designed lens combined with the imaging fiber bundle was established in the software Tracepro. The coupling efficiency of the simulated system is about 96% and the illumination of output end is uniform. All the results show that the designed lens has the peculiarity of wide FOV, short focal length, logical configuration, high coupling efficiency and uniformity illumination at image plane. It is suitable for the fiber-optic endoscope.