Non-tuberculous mycobacterial (NTM) cervical lymphadenitis has been rarely reported in Japan. We report on a case of a 15 month old child with NTM cervical lymphadenitis who was diagnosed with new skin tests containing NTM antigens and a polymerase chain reaction (PCR) method. These two diagnostic methods were highly useful in the present case, therefore we anticipate they will become available to other Japanese physicians to expedite the diagnosis of NTM lymphadenitis.