The enhanced delivery into lymph of bleomycin was studied by i.p. and i.m. injection of oil emulsified preparations. A comparison of concentration of bleomycin in thoracic duct lymph showed that W/O [water in oil] emulsion was the most effective and followed by O/W [oil in water] emulsion. An application of spray drying powder was also attempted to enhance delivery, and the lymph concentration was increased as compared with injection of the aqueous solution, although lower than with O/W liquid emulsion. A measuring of binding to oil particles indicated that .apprxeq. 40% of bleomycin was bound to the particles of O/W liquid emulsion and reconstituted emulsions prepared from drying products. The clearance rates of bleomycin from the muscle were delayed by about 1/2 by W/O, O/W and reconstituted emulsion. The possible mechanism of enhanced delivery into rat lymph was discussed.