Abstract: Effects of different sulphuric acid concentrations, temperatures and durations of prehydrolysis on the dissolvability of hemicellulose in Eucalypiu citriodora chips in prehydrolysis with dilute sulphuric acid were studied, yields, pentosan contents in prehydrolyzed wood chips as well as substances reduced and furfural contents in solutions have been worked out by regression equations. According to the test results and the regression analyses, the optiomal process conditions for dilute acid prehydro-lysifi of Euccelyptu cilriodora chips were as fellow: The ratio of liguor to chips 4:1, the sulphuric acid concentration 0.2%, the highest temperature 135C and the reaction duration 2 hours. Under this conditions, solid content in the acid prehydrolysis solution was 3-4% and xylose showed an approximate 90% of total sugar by the gas chromatography analysis. Prehydrolyzed chips were cooked with sulfate and bleached pulp was obtained by chlorination, alkaline extraction, hypochlorite bleaching and acid treatment. The bleached pulp yield was 32-80%- Contents of ^-cellulose, pentosan, ash and iron in the bleached pulp and the reactivity of the pulp were also determined, which showed that the pulp was suitable for the production of viscose fibres and cellulose derivatives.