In accordance with the high-performance and miniature requirement to pulse microwave source by the Ramsey-coherent population trapping (Ramsey-CPT) atomic frequency standard, a pulse microwave source, with the characteristics of high stability, high resolution, fast frequency hopping speed, low phase noise, miniature, and small scanning step, is realized through direct digital frequency synthesizer (DDS), exciting phase-locked loop (PLL) frequency synthesizer and then connecting the digital step attenuator and the impedance matching circuit. Several schemes of the pulse microwave source for Ramsey-CPT atomic frequency standard are compared. The basic principle and practical method of the pulse microwave source are introduced. The best performance of output signal is obtained by optimizing the simulation result. The pulse microwave source has excellent technical performance, and it further improves the output signal of the CPT atomic frequency standard. Moreover, the overall design comes up to the miniaturized requirement, and is favorable to portable application of the Ramsey-CPT atomic frequency standard.