We introduce a planar, high focusing ability, low loss lens using subwavelength high contrast grating (HCG). After a plane wave passes through the 21.7μm wide HCG lens, it is focused 9.51μm below the lens, resulting an NA of 75%. At the focal plane, it presents a full-width-half-maximum (FWHM) of 0.95μm, which is extremely close to diffraction limit. The transmittance is 88%, which means that the loss due to reflection and absorption is only 12%. HCG focusing optics is defined by one-step photolithography and thus can be readily integrated with many devices including VCSELs, telescopes, CCDs and solar cells.