Thyroid cancer is typically present with euthyroid or clinical/subclinical hypothyroidism. Hyperthyroidism should lead to a lower incidence of thyroid cancer than that observed in euthyroid patients. Thyrotoxicosis with concomitant thyroid cancer is rare and poorly recognized, which may result in delayed diagnosis, inappropriate treatment and even poor prognosis. Thyroid cancer can be associated with Graves’ disease, toxic multinodular goiter, or autonomously functioning thyroid adenoma. The etiology, pathogenesis, diagnosis and treatment of this challenging setting were systematically reviewed in order to provide a comprehensive guidance for clinicians. Medical history, biochemical assessments, radioiodine uptake, anatomic and metabolic imaging and ultrasonography-guided fine-needle aspiration combined with pathological examinations were found to be critical for precise diagnosis. Surgery remains a mainstay of treatment for both pathologies. The objective of this study was to summarize current evidence regarding the association of thyrotoxicosis and thyroid cancer and whether this affects the patient outcome.