Abstract: The present invention proposes an O-band silicon-based high-speed semiconductor laser diode for optical communication and its manufacturing method, by using different buffer layers to form the growth surface of InP material with low dislocation density; N—InAlGaAs is used instead of conventional N—InAlAs electron-blocking layer in the epi-structure to reduce the barrier for electrons to enter the quantum wells from N-type and lower the threshold; a superlattice structure quantum barrier is used instead of a single layer barrier structure to improve the transport of heavy holes in the quantum wells; and the material structure is adjusted to achieve a reliable O-band high direct modulation speed semiconductor laser diode for optical communication on silicon substrate.