Background: Ramie fiber is a kind of natural polymer material with abundant resources and low price

which has been widely applied in textile.Ramie textiles possess many good qualities

such as air permeability

sweat conductivity and antibacterial ability

but the high crystallinity of ramie fiber gives rise to bad spinning property

small extensibility and low chromaticity which restrict its further application.Purpose: In order to reduce the crystallinity of ramie fiber

the electron beam was directly utilized to irradiate ramie fiber.Methods: Ramie fiber was irradiated by electrons with the irradiation doses from 0 to 2 000 kGy

and the irradiated ramie fiber was characterized by XRD and FT-IR.The crystallinity and the crystallinity index of ramie fiber were analyzed

and the irradiation effect was discussed.Results: The crystallinity and the crystallinity index of ramie fiber decrease with the increasing of irradiation doses and the number of-C O increases with the increasing of irradiation doses.Conclusions: The variation behavior of the crystallinity and the crystallinity index of ramie fiber with electron irradiation dose ranging from 0 to 2 000 kGy is got.It is shown that the crystallinity and the crystallinity index of ramie fiber may be effectively reduced by using electron beams irradiation

but also the required crystallinity of ramie fiber in its application can be achieved by controlling the electron beams irradiation doses.