Abstract: The misdiagnose cause of 45 patients with abdominal malignant lymphome of being initially diagnosed as the tubercle mass,meet in our hospital between 1988 and 1992 were analiged.The ineligible collection of clinic document,including the special symptom and sign on the past history about the tuberculosis;the preferance of diagnoses to the malignant disease for some oncology medical,and the deficiency of knowledge about the characteristic image of echography for these mass in the abdominal cavity were important facfion of the misdiagnoses.This paper suggest that it is reason to perfer the diagnoses of the tubercle mass to the malig-nant disease for a mass in the abdominal cavity if the patient is younger than 40-year-old with the characteristic symptom and for the past history about the tuberculoscis,and if the patient has a abdominal mass smaller than 5 cm of maximum diameter.