This investigation aimed at improving the quality of domestic Angora fur fibre, when it is spun together wool and synthetic fibre, by solving the difficulties in processing and it was also aimed at finding the methods of preventing the fault of fibre-slipping off from knitted goods. This investigations was classified into two main parts, one of them was fundamental study and another was spinning and knitting performance. In the former the physical and chemical properties was investigated, in the latter the spinning and knitting performances was investigated taking use of the results of fundamental study. The processing aspects was, in the study of spinning and knitting performance, compared with the quality of trial-products which was made during the investigation and the method of preventing fibre-slipping off was also studied. Summary of results were as follows; 1) Topology of Angora fur fibre circled1 Generally Angora fur fibre was classified into three appearances, finer fur fibre, hetero type hair and guard hair. circled2 Angora fur fibre, regardless of its appearances, was composed of ladder type medulla forming a hollow cylinder and covered with cortex. circled3 A few crimps was founded in Angora fur fibre except finer fur fibre. circled4 Though the scale on the Angora fur fibre was founded, it was exceedingly by smaller than that of woo. 2) Physical properties circled1 Because of characteristics in appearances of Angora fur fibre the strength-elongation behaviour was considerably scattered and load-elongation behaviour of finer fur fibre was less than that of wool. circled2 The static charging rate of Angora fur fibre was similar to that of wool but discharging rate was quicker than that of wool. circled3 The staple length of domestic Angora fur fibre was considerably scattered. 3) Chemical properties circled1 The chemical component of Angora fur fibre was similar to that of wool. circled2 Rate of curl was increased by the treatment of carroting but the load-elongation behaviour became 4) Spinning and knitting performance circled1 Smaller amount of water was recommanded when oiling the Angora fur fibre than oiling the wool. circled2 The processing characteristics of Angora fur fibre was similar to that of wool which has fine denier and long staple. circled3 Knitting officiency could be increased by the use of additional filament yarn. 5) Fibre-slipping off from the knitted goods circled1 The mechanism of fibre-slipping off was classified into two parts, fibre-slipping off by statics and frictional pulling. circled2 a) The prevention of fibre-slipping off was capable by increasing of twists, turns Per unit length of yarn and using of long staple. b) The use of core yarn was effected on the decrease of fibre-slipping off.