Medullary Thyroid Carcinoma (MTC) is a rare tumor of Para follicular cells of the thyroid gland. It can occur sporadically or maybe inherited as a component of MEN syndromes. When diagnosed during pregnancy, the timing of surgery is essential since maternal thyroxin is vital for fetal nervous system development. A 34 years old pregnant woman was diagnosed with MTC at her 17th week of pregnancy. Her Calcitonin level was elevated, while her CEA level was average. She underwent total thyroidectomy with a total lymph node dissection during the second trimester of pregnancy. After surgery, her calcitonin level dropped to the normal range. Levothyroxine treatment had initiated right after the surgery to prevent fetal complications. Calcium and active vitamin D3 supplementation were added. The patient gave birth to a term healthy infant. With this case report, we aim to share our experience in managing MTC in a pregnant woman till the birth of the infant.