In this paper, both glyoxal bis(4-phenyl-3-thiosemicarbazone) (GBPT) and bathocuproine disulphonate (BCDS) methods for copper have been applied to the spectrophotometric determination of copper in foods, feedingstuffs and plants. Results obtained in both cases are typical of those expected for good spectrophotometric procedures. However, the GBPT method affords the distinct advantage of direct use in acidic solution without the necessity of neutralization and pH adjustment, being thus more satisfactory for unskilled usage.