Abstract: The crystal of anemonin, C₁₀H₈O₄, which is colorless and transparent,belongs to orthogonal system with space group D_2h¹⁵-P2₁/b2₁/c 2₁/α, The unit cell parameters are α= 11.063(4),6 = 11.633(4),c = 13.873(4)Å,Z=8.The diffractometry result shows that the two unsaturated γ-lactone rings are connected to cyclobatane at 1,2 positions in a spire arrangement. It is the same as the result of spectra determination.