Abstract: Objective This paper work aims to analyze the nutrition of retreated smear positive tuberculosis patients treated in 2012—2013. In addition, the relationship between malnutrition and tuberculosis retreatment was discussed. Methods We observed nutritional status of the retreated smear-positive patients through measurement of serum protein, erythrocyte count, and hemoglobin of 145 cases of retreated smear positive patients and 105 newly diagnosed smear positive patients during their first visit to Guangzhou Thorax Hospital Clinic Ⅱ. The serum total protein, albumin, globulin, A/G ratio, total number of red blood cells, lymphocyte count, hemoglobin values was compared between new and retreatment patients by using Chi-square test, P<0.05 was considered statistically significant.  Results Among 105 new smear-positive patients, the total protein decreased in 22.86% (24/105) of patients, albumin and globulin reduced in 20.00% (21/105) and 17.14% (18/105) of patients respectively, A/G ratio, red blood cell count, hemoglobin and lymph cells reduced in 34.29% (36/105), 24.76% (26/105), 47.62%（50/105） and 2.86% (3/105) of the patients respectively; Of the 145 retreated patients, the total protein decreased in 22.76%（33/145）of patients, albumin and globulin reduced in 22.76%（33/145） and 24.83%（36/145） of patients respectively, A/G ratio, red blood cell count, hemoglobin and lymph cells reduced in 51.72%（75/145）, 26.90%（39/145）, 33.10%（48/145） and 3.45%（5/145） of the patients respectively; The decreasing proportion of A/G ratio and hemoglobin is statistically significant different between new and retreated patients (χ²=7.502, 5.384, P<0.05). The decreasing proportion of total protein, albumin, globulin, red blood cell count, lymph cells did not show significant different between two groups（χ²=0.000，0.274，2.124，0.144，0.069，P＞0.05）.  Conclusion Lower serum protein A/G ratio is high risk factor of retreatment of tuberculosis.

Key words: Tuberculosis, pulmonary/Blood, Blood proteins