The work aims to take Hainan rubber wood as the raw material to determine the content of its chemical components (ash, holocellulose, lignin, hemicellulose, α-cellulose, 1% NaOH extract, phenyl alcohol extract, starch and protein), observe and study its microstructure and compare it with typical hardwood poplar and birch, to clarify its chemical components and microstructure characteristics. Plant microscopic techniques and Chinese national standards for chemical component determination were used in combination for analysis. The lignin, holocellulose, ash, hemicellulose, α-cellulose and extracts of Hainan rubber wood were slightly different from those of hardwood poplar and birch, but its starch and protein content were much higher than those of typical hardwood poplar and birch. The fiber length of rubber wood was 1 176.68 μm, the width was 21.35 μm, the aspect ratio was about 55.11, and the cell ratio was 0.49. Rubber wood was a diffuse porous wood. The wood ray structure was heteromorphic I and heteromorphic Ⅱ. The wood fibers were tracheid and keratinous wood fibers. The axial parenchyma had two types:adjacent parenchyma and off-tube parenchyma. The higher content of cellulose and lower content of lignin and phenyl alcohol extracts, the larger aspect ratio and the smaller cell ratio make the rubber wood pulp process consume less delignification and bleaching agents, so the streaming time is shorter, pulping yield is higher, fiber intertwining ability is stronger, fiber distribution is denser and paper binding strength is higher. It is more suitable as an important substrate for the preparation of paper-based packaging materials with excellent mechanical properties.