Aiming at the microwave photonic system’s demand for on-chip high-speed modulation devices，based on the linear electro-optic effect of lithium niobate materials，this research carried out the optoelectronic co-simulation design of on-chip devices and used the semiconductor device preparation method compatible with the CMOS process. On-chip optoelectronic devices such as low-loss lithium niobate waveguide，high-efficiency coupling mode spot converter，and highfrequency microwave signal transmission line are integrated on the lithium niobate（LNOI）wafer on the insulator to realize the on-chip integration of the modulator chip. The coupling process using micro-optics realized the optical signal input and output of the optical fiber array on the chip；the impedance matching of the chip-thin film resistor-RF joint and the low-loss transmission of electrical signals were realized by wire bonding；Hermetic packaging was used to improve the reliability and environmental adaptability of the modulator. The test showed that the optical power insertion loss of the device is <6.5 dB， the modulation bandwidth is >15 G（@3 dB），and the dynamic half-wave voltage is <6 V（@10 GHz），meeting the application requirements of photoelectric oscillators and other related microwave photonic devices.