Ovarian cancer in pregnancy is a rare occurrence. Of all ovarian malignancies, <1% comprise immature teratomas. We present the case of a 24-year-old primigravid with an incidental finding of an ovarian new growth during a routine first-trimester ultrasound. The mass was suspicious for malignancy due to an ultrasound finding of a cystically enlarged 8.2 cm × 5.8 cm × 6.2 cm mass, with solid components and with minimal color flow on Doppler. There was an interval increase in the said mass during the second trimester, with an elevated alpha-fetoprotein (AFP) level. The patient underwent surgery at 24 weeks gestation. Histopathology revealed Immature Teratoma, FIGO Grade 3, stage IC1. She delivered to a live, term baby boy through cesarean delivery. Postpartum, she completed four cycles of chemotherapy using bleomycin, etoposide and cisplatin (BEP), and was advised surveillance with serum AFP every 3 months. Due to the limited number of cases of ovarian cancer in pregnancy reported, management is individualized. Dilemma in terms of the timing of surgery, neonatal and maternal outcomes, timing and mode of delivery, and control of tumor metastasis through chemotherapy were met, hence, a multidisciplinary team and patient decision is crucial to achieve successful and desirable outcomes for the mother and the fetus. This is the first case of immature teratoma in pregnancy reported in our institution and in a local setting.