The invention relates to a solar heat collector with a focusing element, and in particular relates to a large-capacity high-concentrating ratio composite Fresnel line concentration reflection device. The large-capacity high-concentrating ratio composite Fresnel line concentration reflection device is structurally characterized in that a main reflection device comprises a plurality of microarc Fresnel reflection lenses which are used as main reflection mirrors, a steering device is arranged at the center of each Fresnel reflection lens, the plurality of Fresnel reflection lenses are positioned above a heat collection pipe and distributed in an arc shape by taking the heat collection pipe as a circle center, the large-capacity high-concentrating ratio composite Fresnel line concentration reflection device further comprises an auxiliary reflection device which is arranged under the heat collection pipe, and an arc-shaped convex surface (concentrating surface) faces towards the direction of the heat collection pipe. The large-capacity high-concentrating ratio composite Fresnel line concentration reflection device has the advantages of obtaining larger ground utilization ratio, adequately considering the incident conditions of sunshine, greatly reducing the sunshine loss, improving the heat collection effect of the heat collection pipe, realizing good focusing effect as well as effect of leading the heat collection pipe to be evenly heated, and showing the large-capacity concentrating effect.