卫星通信系统具有长的传播时延，其随机多址协议性能的改善非常困难。针对长传播时延的通信系统， 我们提出了一种分优先级的ＡＬＯＨＡ 协议。研究结果表明，这种协议可以以较小的代价简单有效地改善卫星随机多址系统的时延性能。文章给出了协议性能与设计参数选择的关系。 Satellite communication systems have long propagation delays and their performance in random multiple access protocols is very difficult to improve. For communication systems with long propagation delays, we propose a prioritized ALOHA protocol. The results show that this protocol can reduce the delay performance of satellite randomized multiple access system simply and effectively with less cost. The article gives the relationship between protocol performance and design parameter selection.