Two methods for spectrophotometric determination of chlorprothixene and amitryptyline hydrochlorides were proposed. One of them is based on spectral analysis of their derivative spectra. The measurement of the value at 316.0 nm of first derivative was used for construction of calibration graph for chlorprothixene. The Beer law was obeyed in the concentration range 0.5-50.0 microg ml(-1). The amplitude of the second derivative at 261.4 nm was used for determination of amitryptyline in the range 0.5-75.0 microg ml(-1). The second proposed method is utilized the use of solid sorbent for simultaneous preconcentration and assay of studied compounds. For this purpose the filtration gel Sephadex G100 was applied. The elaborated solid-phase spectrophotometric method was used for determination of chlorprothixene at 268.0 nm in the range 2.5-75.0 microg ml(-1) and amitryptyline at 238.0 nm in the concentration range 10.0-75.0 microg ml(-1).