The invention discloses an image space telecentric direct writing projection imaging objective lens for excimer laser microprocessing, and belongs to the technical field of laser microprocessing and application thereof. The object space field and the image space field are in reduction scale. In the range of the object space field, all the principal rays, except the principal rays on the axis, irradiate on a projection object plane at a certain angle; and in the range of the image space field, all the principal rays are vertically incident to an imaging image surface. The structural form is divided into two parts: the first part consists of a fused quartz lens, wherein the lens adopts the structural form of a biconvex lens; and the second part consists of four fused quartz lenses, wherein the first lens adopts the structural form of a biconvex lens, the second lens adopts the structural form of a left concave lens and a right convex lens; the third lens adopts the structural form of a biconvex lens, and the fourth lens adopts the structural form of a left convex lens and a right concave lens. The image space telecentric direct writing projection imaging objective lens effectively improves the condition that the processed lower surface pattern is deflected to the outer side of an optical axis relative to the processed upper surface pattern of a processed workpiece, which is caused by the conventional direct writing projection imaging lenses for the excimer laser microprocessing.