Aiming at the problem that the current optical transmitter of digital temperature control introduces the stray interference signal that can not be eliminated, an analog temperature controled microwave optical transmitter with the characteristics of simple circuit, small structure and low power consumption is designed, and the composition of the optical transmitter and the detailed design circuit of each module are given. According to the principle of direct modulation, a microwave link simulation test system is built, and the important index parameters such as S scattering parameters, spurious suppression ratio, harmonic suppression ratio and system noise coefficient of the simulated temperature controlled optical transmitter are tested. The test results show that the link gain of S scattering parameters is greater than or equal to -25 dB, and the gain flatness is ±2 dB. When the spurious suppression ratio is greater than 90 dB, the spurious signals are basically submerged in the background noise of the system. The harmonic suppression ratio exceeds 50 dB and reaches about 67 dB. The noise coefficient is controlled at the level of 2 GHz@35 dB–18 GHz@56 dB, which fully meets the practical requirements.