The invention provides a five-segment type InP-base single-chip integrated tunable inclined cavity laser chip and a manufacturing method thereof. The method comprises the following steps: selecting an indium phosphide substrate; growing a primary epitaxial structure on the indium phosphide substrate, wherein the primary epitaxial structure comprises a buffer layer, a quarternary lower waveguide layer, a multi-quantum well layer, a quarternary upper waveguide layer, a corrosion stop layer and a grating layer; etching a grating tuning area and a phase matching area on the primary epitaxial structure and growing a passive waveguide layer in a butt-joint growth method; manufacturing a part of a grating on the passive waveguide layer by use of a silicon dioxide mask selective area growth drying-wetting method and burying the part of the grating; etching an electroabsorption outer modulation area on the primary epitaxial structure, growing a lower waveguide layer, a multi-quantum well layer and an upper waveguide layer of an electroabsorption outer modulation layer in butt-joint growth method, and burying the lower waveguide layer, the multi-quantum well layer and the upper waveguide layer of the electroabsorption outer modulation layer; manufacturing an inclined ridge waveguide on a chip and growing an optical restriction layer and an electrical contact layer in a buried mode; manufacturing a P-surface electrode on the electrical contact layer, and manufacturing an N-surface electrode on the back surface of the chip; and performing film plating, and cleaving to form a single chip so as to complete manufacturing of the laser chip.