Abstract: Beaver livesby Wulungu river and its branch in northern Xinjiang province and it has been investigated during late autumn and early winter of 1988．The body weight of adult beaver is 24.1±1.9kg，body length 83.4±2.9cm，tail length 27.3±0.5cm ，cranium length 142.6±2.4mm and zygomatic width 102.8±2.4ram．The body weight of subadult beaver is 16.0±1.7kg．
The fur size of adult and subadult beaver is 177.8cm and 152.1cm .the dry castor sac of adult and subadult is 190.60± 49.78g, and 59.95±9.46g，respeetively．The net castor weight of adult is five times than that of subadult．
The ralationships between body weight and dry castor sac size，and between castors size and castorium content ratio are positively correlated．Regression equations of the former and the latter are V= -145.35+13.49x and y=0.6066+0.013x，respectively．
Xindiang beaver families are in the underground nests．They don't built the damas usua1 and the territorial behavior has been found in beaver．The distance between both nests is about 1-2 km ．
The population of beaver have been estimated．About 600-700 beavers live in northern Xinjiang province．Four suggestions for protecting Xinjiang beaver were put forward in this paper．

Key words: Xinjiang beaver, Castor, Habit

摘要： 1988年秋末冬初，对新疆乌伦古河及其支流的河狸进行了调查。成体河狸体重24.1±1.9千克；体长83.4±2.9米，尾长27.3±0.5厘米；颅全长142.6±2.4毫米，颧宽102.8±2.4毫米；亚成体体重16.0±1.7千克，香囊干重分别为190.60±49.78和59.95±9.46克，成体净香量(147.5克)是亚成(28.85克)的5倍。河猩体重与香囊干重，以及香囊干重与含香率都呈正相关，回归方程前者是Y=-145.35+13.49x(r=0.79)；后者是Y=0.6066+0.0013x(r=0.8839)。
新疆河狸现存量60O-7O0头，本文对河狸保护提出4项建议。

关键词: 新疆河狸, 河狸香, 习性