给出了半导体激光（ＬＤ）放大器的电路模型，使得对半导体激光放大器的特性可以用通用电路分析软件进行分析。用该模型对谐振型光放大器光功率输出特性与失谐关系进行了模拟分析，模型的分析结果与已报道的理论和实验基本一致；用该模型还对谐振光放大器的噪声进行了分析。 The circuit model of semiconductor laser (LD) amplifier is given, and the characteristics of the semiconductor laser amplifier can be analyzed by general circuit analysis software. The model was used to simulate the optical power output characteristic and detuning relationship of the resonant optical amplifier. The results of the model analysis are basically the same as the reported theoretical and experimental results. The noise of the resonant optical amplifier is also analyzed with this model.