Two crystalline compounds (A and B) were obtained from the fresh leaves of Cirsium arisanense Kitam (Compositae) by the separation method described in the experimental part. Compound A was crystallized from methanol as colorless needle with mp 254-255° (decomp.) and C29 H340 O15‧H2 O. It exhibited orange-red color with Mg+HCI,violet-red with Zn+HCI and green-brown with FeC13 and was positive with Fehling's solution. The ultraviolet (UV) absorption curve, which is similar with the flavone compounds, has maximum absorptions at 275 (4.26) and 330 (4.37) mμ(log ε). The infrared (IR) spectrum (KBr) indicated the presence of a conjugated ketone group at 1670 cm-1. Hydrolysis of compound A with 36﹪ HCl afforded pectolinarigenin (I), an yellow crystal with mp 214-215°, which was identical (mixed mp and IR spectrum) with authentic sample provided by Dr. N. Morita. University of Toyama, Japan and two monosaccharides, glucose and rhamnose, their osazones were identical (mixed mp and IR spectrum) with authentic glucosazone and rhamnosazone, respectively. From these data compound A was assumed as pectolinarin 2) (pectolinarigenin-7-rutinoside) (II) and it was proved by mixed melting point and comparison of IR spectra (KBr) with authentic sample. Compound B was obtained as colorless needles with mp>300° (from methanol) and C4H4O4 and was identical (IR spectrum) with authentic fumaric acid (III).