We report two patients with postoperative deep mycosis. An 81-year-old and a 71-year-old woman respectively developed fever associated with elevated serum CRP 3 and 19 days after esophageal surgery. Adminstration of antifungal agents was commenced upon finding a high serum concentrations of (1→3) -β-D-glucan and positive cultures for Candida. However, β-D-glucan concentrations continued to rise. Changes in β-D-glucan concentrations showed no relationship to those in CRP or the clinical course in either patient. Soon CRP and clinical findings improved with treatment adjustments concerning antifungal agents. Antifungal therapy was subsequently ceased while β-D-glucan concentrations remained higher level than normal. Both patients were stable after cessation of antifungal therapy and were discharged in good clinical condition. It was difficult to ascertain whether such elevation in β-D-glucan concentrations resulted from persistant fungal infection or false positive. The present cases and some previous reports suggest that antifungal therapy can be ceased when the clinical condition has clearly improved and the serum concentrations of β-D-glucan tends to decline, even though it remains higher level than normal.