Ovarian small cell carcinoma of hypercalcemic type is a rare neoplasm that typically occurs in young females. We describe three cases of ovarian small cell carcinoma of hypercalcemic type occurring in patients aged 24, 37, and 25 years. The first patient had stage IIc disease and had primary surgery with a left salpingo-oophorectomy and omentectomy, followed by chemotherapy with cisplatin and etoposide. Upon a second relapse, pelvic lymphadenectomy was performed, followed by chemotherapy with docetaxel. She is alive for 4 years without any recurrence after the initial treatment. In vitro drug-sensitivity assay revealed the tumor cells were sensitive to taxane and resistant to irinotecan. The second patient had stage III disease and had primary debulking surgery with bilateral salpingo-oophorectomy, simple hysterectomy, omentectomy, low-anterior resection, and lymphadenectomy, followed by chemotherapy with paclitaxel and carboplatin. Four months after the initial treatment she relapsed and died. The tumor cells were sensitive to platinum, taxane, and doxorubicin, but resistant to irinotecan. The third patient had stage III disease and had right salpingo-oophorectomy, omentectomy, and lymphadenectomy, followed by chemotherapy with cisplatin, cyclophosphamide, and doxorubicin. She relapsed 4 months after completing the chemotherapy and died 5 months after secondary debulking surgery. The tumor cells were sensitive to platinum, taxane, and doxorubicin, but resistant to irinotecan. The drug-sensitivity assays suggested that a non-irinotecan, taxane-containing combination might have been suitable as first-line chemotherapy for these patients. However, an effect of such a regimen was seen in only one patient with early-stage disease, and this questions the validity of chemosensitivity testing.