The first isolation of naturally occurring salicylamine and its Schiff base, 2-hydroxy-N-(2'-hydroxybenzylidene)-benzylamine and the co-existence of free 4-hydroxybenzylamine in the achenes of Fagopyrum esculentum Moench which are commonly used as human food in Japan, have been described. The structural confirmation of these compounds as carried out on the basis of the elementary analyses and spectroscopic properties and, eventually, by comparison with authentic specimens, if necessary. During an investigation of non-protein amino acid fraction of buckwheat seeds, several unusual spots, giving rise to a yellow color with ninhydrin which subsequently turn purple on paper chromatogram, were observed. Furthermore, their behaviour on ion-exchange resins is suggestive of basic amphoterites and amines. The two major constituents of these basic substances have now been isolated in the crystalline state from aqueous alcoholic extracts of buckwheat seeds and their structures were established as salicylamine and 4-hydroxybenzylamine, respectively. It was also observed that the hydroxybenzylamines are subject to autoxidation with presumable formation of polymers in various stages. On the crystallization of sublimates of the hydroxybenzylamines from absolute ethanol and petroleum ether, the mother liquor of 4-hydroxybenzylamine produced brown colored oily residue which progressively turned darkred or -brown amorphous precipitates in aqueous alcoholic solution, being allowed to stand for some time in contact with air. In the case of the isolated salicylamine fraction, the yellowish brown residue on sublimation gave yellow needles, after crystallization from ethanol or chloroform, which fluoresced a light yellow color on exposure to ultraviolet light. The resulting crystals which possessed the elementary composition C14H13NO2, was characterized as a Schiff base of salicylamine, 2-hydroxy-N-(2'-hydroxybenzylidene)-benzylamine on the basis of its spectroscopic properties. While the free hydroxybenzylamine in higher plants has previously been encountered only in seeds of Sinapis alba L., the naturally occurring salicylamine and its Schiff base have been isolated for the first time from achenes of Fagopyrum esculentum Moench which are commonly consumed as human food in Japan.