用多聚酶链反应（ＰＣＲ）技术、引物标记周期反应测序法和自动核酸序列分析仪直接测定我国和３个西太平洋国家共１８个间日疟分离株的环子孢子蛋白（ＣＳＰ）基因两侧翼ＤＮＡ序列，并与ＢＺＬ、Ｂｅｌｅｍ、Ｓａｌ－１、Ｎ．Ｋ．和Ｔｈａｉ等地区株进行比较。结果表明不同地区间日疟ＣＳＰ基因Ｎ端和Ｃ端非重复序列高度保守；１８个分离株与５个地区株的上述序列基本一致。但在Ｃ端可变区则有较多变异，包括一些尚无记载的地理局限性变异。 Polymerase chain reaction (PCR), primer-labeled periodic reaction sequencing and automated nucleic acid sequence analyzer were used to directly detect the DNA flanking the circumsporozoite protein (CSP) gene of 18 P. vivax isolates in China and three Western Pacific countries Sequence, and with BZL, Belem, Sal-1, N. K. And Thai and other regional strains for comparison. The results showed that the N-terminal and C-terminal non-repetitive sequences of CSP gene of P. vivax in different regions were highly conserved. The sequences of the 18 isolates were consistent with those of the five regions. However, there are more variations in the C-terminal variable region, including some unremarkable geographical variation.