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We experimentally generated high-order harmonic with minimized angular divergence by using a truncated Bessel (TB) beam which propagates through the optical elements with finite aperture size.The TB beam was first discovered by M.Nisoli et al.[Phys.Rev.Lett.88, 3 (2002)]; it is generated from a hollow fiber.In their paper all the optical elements are considered as infinite size, so the fast oscillations of the light filed exist near the laser focus point.We took the finite size of the optical elements into account and found that those oscillations vanisl.The TB beam has two intensity peaks around the focus point.Just in the front of the second peak point, the curvature of the laser phase front cancels that of the atomic-dipole phase front, so the high-order harmonic has a fiat phase front and has a minimized angular divergence at far-field The analysis is supported by both the simulation and experiment.