Psychiatric studies were made on 26 inoperable patients with lung cancer or thymic cancer to exam the possible correlation of chemotherapy and chemotherapy-induced nausea and vomiting. All patients were informed of their disease and how to undergo the therapy. Psychiatric tests of CMI (Cornell Medical, Index), MAS (Manifest Anxiety Scale), SDS (Self-Rating Depression Scale) and QOL questionnaire were performed just before the chemotherapy. SDS and QOL questionnaire were also done after chemotherapy. The patients were given chemotherapy including CDDP (80 mg/m2) and anti-emetic agents of 30 mg of azasetron, 750 mg of methylprednisolone and 1,800 mg of domperidone. The patients showing neurosis, anxiety or depression had significantly high nausea scores, so we concluded that psychiatric support was needed to improve these patients' QOL in chemotherapy.