Mycoses refer to infectious diseases caused by fungi. Fungal infections are rare and mainly occur as opportunistic infections in immunocompromised patients. Candida species are the most common cause of mycosis; however, members of the order Mucorales or genus <i>Aspergillus</i> may also cause serious fungal infections in immunocompromised hosts. Fungal infections of the gastrointestinal (GI) tract can be asymptomatic or may present with abdominal pain, bloating, diarrhea, or GI bleeding. Although rare, thorough understanding of fungal infections of the upper GI tract encountered in real-world clinical settings can enable early diagnosis and prompt initiation of treatment to improve patient prognosis.