目的 研制胎龄25~40周双胎儿出生体重曲线，并探讨其地区差异特征。 方法 在中国11市（海口、广州、柳州、桂林、泉州、深圳、重庆、成都、长沙、宁波、连云港）选择年分娩量7 000例以上的11家妇幼保健院，纳入其2017年1月1日至2020年12月31日分娩的全部活产双胎儿进行出生体重曲线研制。 结果 纳入了上述11市合计17 256例胎龄25~40周双胎儿进行研究，建立了中国11市合计及各市双胎儿出生体重第3~97百分位数参考值，并绘制了出生体重百分位曲线图。柳州市双胎儿出生体重曲线水平低于11市合计双胎儿；宁波市双胎儿出生体重曲线水平高于11市合计双胎儿；连云港市双胎儿出生体重曲线水平明显高于11市合计双胎儿；其他8个城市双胎儿出生体重曲线水平与11市合计双胎儿曲线水平基本一致。 结论 制定了中国11市合计及各市双胎儿出生体重第3~97百分位数参考值，可作为该区域双胎儿宫内生长评价的参考标准。部分城市双胎儿宫内生长水平与中国11市合计的水平存在差异。

Objective To develop the birth weight curve of twin neonates with a gestational age of 25-40 weeks, and to investigate the regional differences of the birth weight curve. Methods A total of 11 maternal and child health care hospitals with more than 7 000 neonates delivered annually were selected in 11 cities of China (Haikou, Guangzhou, Liuzhou, Guilin, Quanzhou, Shenzhen, Chongqing, Chengdu, Changsha, Ningbo, and Lianyungang), and all live twin neonates delivered in the 11 hospitals from January 1, 2017 to December 31, 2020 were enrolled for the development of birth weight curves. Results A total of 17 256 twin neonates with a gestational age of 25-40 weeks from the 11 cities were included in the study. The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities in China were established, and the birth weight percentile curves were drawn. The birth weight curve level of twin neonates in Liuzhou was lower than the average level of the 11 cities; the birth weight curve level of twin neonates in Ningbo was higher than the average level of the 11 cities; the birth weight curve level of twin neonates in Lianyungang was obviously higher than the average level of the 11 cities; the birth weight curve level of twin neonates in other 8 cities was almost the same as the average level of the 11 cities. Conclusions The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities are developed, which can be used as a reference for evaluating the intrauterine growth of twin neonates in the region. The level of intrauterine growth of twin neonates in some cities is different from the average level of the 11 cities of China.