Abstract: icrocapsules containing paraffin as core and SiO₂ as shell were synthesized in-situ in polyvinyl alcohol (PVA) spinning solution. Thus energy storage paraffin/PVA fibre was prepared via wet-spinning process. To get the optimum conditions for the synthesis of microcapsules, the orthogonal experimental design was used together with the particle size analysis software to analyze relevant factors of particle size. Chemical structures and morphologies of the microcapsules and the fibres were characterized by FTIR-ATR, SEM, EDS and TEM. DSC and TGA were adopted to determine the coated rate of microcapsules, the latent heat storage and thermal stability of the fibre. The results indicate that energy storage microcapsules are successfully synthesized in PVA spinning solution with a paraffin encapsulated ratio as high as 94.72%, and the average particle size of 1.39 μm is suitable for wet-spinning. The paraffin/PVA fibre shows a relatively good thermal stability with a high latent heat of 45.39 J/g.