High-power photoconductive semiconductor switch (PCSS) working in linear mode can be used for RF generation by modulating the illuminating light. This letter presents a design and initial test of an optoelectronic class B push-pull microwave power amplifier (MPA) using two 6H-SiC photoconductive switches. The initial tests have been conducted with bias voltage of ±2.4 kV, at 80 kW peak laser pulse power, demonstrating that the SiC PCSS working in linear mode can produce microwaves. Then, circuit simulation is conducted to study the factors affecting the electrical efficiency, such as the quantum efficiency, the peak laser pulse power, and the bias voltage. It is speculated that the MPA could output 1 mW microwave power and achieve electrical efficiency of more than 60% with a bias voltage of 15 kV, quantum efficiency of 0.2, and peak laser pulse power of 100 kW.