In the fusion field of optoelectronics and microwave technology, Microwave Frequency Comb (MFC) is a kind of crucial high-precision measurement and signal processing tool, and its continuous optimization has been the core issue of scientific research and technical development. With its precise frequency interval and wide coverage, MFC has shown great application potential in many fields such as wireless communication. However, most of the traditional MFC techniques rely on electric filters for frequency selection, leading to unstable frequency comb interval, frequency drift, and vulnerability to electromagnetic interference. These problems are especially prominent in precision measurement and high-speed signal processing scenarios, which limits the further improvement of MFC performance and the expansion of application range. In this paper, an Active Mode-Locked Optoelectronic Oscillator (AML-OEO) based on stimulated Brillouin scattering is proposed. The Stimulated Brillouin Scattering (SBS) and the optoelectronic oscillator are used in the experimental device, and the active mode-locking technology is innovated used to generate the high flatness microwave frequency comb.The main frequency oscillation of the microwave frequency comb is realized by the selective sideband amplification characteristic of stimulated Brillouin scattering in highly nonlinear optical fibers. The active mode-locking of the microwave frequency comb is generated by injecting an external modulated signal to the Mach-Zehnder modulator. Compared with the traditional method, the OEO uses SBS instead of the electric filter, which not only avoids the frequency drift problem, but also improves the stability and flatness of the MFC. The center frequency of this optoelectronic oscillator is determined by the Brillouin frequency shift, therefore, it is only necessary to simply adjust the output frequency of the semiconductor laser to achieve the tuning of the center frequency. By injecting the same external microwave signal as the Free Spectrum Range (FSR), the mode locking is realized, the MFC with adjustable center frequency and high flatness is generated. By varying the output wavelength of the tunable laser and the length of the delayed fiber, the generated microwave frequency comb can be tuned within a range of 307.1 MHz, which is determined by the gain bandwidth of the EDFA. But outside this range, as it is not within the gain bandwidth of the EDFA, the pump power is reduced, and a stable frequency comb cannot be formed, therefore, EDFA is the key device in the experimental device. In addition, through changing the length of the OEO cavity, adding a delay optical fiber with a length of 30 m, 300 m and 650 m in the loop, the MFCs with different frequency intervals of 202.92 kHz, 190.42 kHz and 123.19 kHz have been obtained, the relationship between cavity length and microwave frequency comb interval is inversely proportional. The stability of the frequency comb with center frequencies of 9.207 4 GHz and 9.514 5 GHz is also measured in the experiment. By measuring the frequency variation within 30 minutes at 5 minute intervals, it is proved that the proposed microwave frequency comb based on stimulated Brillouin scattering photoelectric oscillator has good stability and the superiority of stimulated Brillouin scattering based AML-OEO.The AML-OEO technique based on SBS effect proposed in this paper provides a novel and effective method for the generation of MFC. The proposed method reveals a method for generating microwave frequency combs with different intervals, which has potential applications in the field of high-precision measurement. The design of AML-OEO will be further optimized and improved to further broaden the tuning range of MFC, improve its flatness and stability, and better meet the needs of more diverse application scenarios. The proposed AML-OEO technology is expected to promote the development of the intersection of optoelectronics and microwave technology.