Although the association of coronavirus disease 2019 (COVID-19) and thromboembolic disease is well known, cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mechanical valve thrombosis have not been described enough. Mechanical valve thrombosis is a medical emergency that is associated with a great impact on patients' morbidity and mortality. Here, we report a case of a patient with mechanical valve thrombosis secondary to SARS-CoV-2 infections that required valve replacement with satisfactory postoperative recovery. A 52-year old female patient was presented with a previously implanted mechanical prosthesis (type - St. Jude Medical 29 mm; St. Paul, MN: St. Jude Medical, Inc.) eight years ago due to rheumatic fever, under anticoagulation with warfarin and valvular atrial fibrillation (permanent), congenital single kidney (glomerular filtration rate {GFR}: 89.9 mL/min), and hypothyroidism. She was admitted to the hospital with a high level of complexity due to respiratory difficulty and generalized edematous syndrome, and a reverse transcription-polymerase chain reaction (RT-PCR) confirmed COVID-19 infection (20 days before admission); the patient was anticoagulated with warfarin (international normalized ratio {INR} at admission was 2.63 seconds). As per protocol, a CT-chest scan tomography was performed and showed organized pneumonia in the right apical lobe. We performed a transesophageal echocardiogram, which showed a thrombus (20 x 15 x 20 mm) in the lateral disc of the mechanical prosthesis, restricting its mobility. The patient presented signs of hypoperfusion (lactate levels: 4 mmol/L; urine per hour: 1 cc/kg) with associated low cardiac output syndrome, requiring double vasopressor support at the maximum dose (achieving a mean arterial pressure of 72 mmHg) due to the clinical condition and the large size of the thrombus, the cardiovascular surgeon, in agreement with the family, decides to carry out emergency valve replacement surgery with replacement of a mechanical prosthesis replacement (St. Jude No. 29; St. Paul, MN: St. Jude Medical, Inc.). The patient presented a satisfactory postoperative recovery, achieving INR goals, with subsequent discharge and follow-up at two months with transthoracic ultrasound, where normofunctional mitral prosthesis was demonstrated, without evidence of thrombi or intracavitary masses. Mechanical mitral valve thrombosis, secondary to SARS-CoV-2 infection is a serious complication with poor prognosis that requires a high rate of suspicion, and timely diagnostic aids are essential to confirm the diagnosis. Managing this issue should be interdisciplinary and individualized considering the clinical condition of the patient and the associated comorbidities.