Background/aim: Our study aimed to investigate a reliable diagnostic approach for tuberculous peritonitis (TBP) by comparing the commonly used diagnostic tools. Materials and methods: Fifty-one patients had received a series of diagnoses, including laparoscopy, erythrocyte sedimentation rate (ESR), cancer antigen 125 (CA125), tuberculin skin test, tuberculosis antibody in serum (TB-Ab), the T-SPOT.TB test, or adenosine deaminase (ADA) in ascitic fluid. The positive rate of each method was calculated and the differences of positive rates between laparoscopy and laboratory tests that had higher positive rates were analyzed by McNemar chi-square test. Results: The most common symptoms and signs of 51 patients were fever (86.3%), abdominal mass (78.4%), abdominal distension (62.7%), abdominal pain (74.5%), and weight loss (66.7%). Furthermore, the positive rates of CA125, laparoscopy, T-SPOT.TB test, and ESR were relatively higher than those of the other three methods (tuberculin skin test, TB-Ab, and ascitic ADA). Additionally, there was no significant difference (P > 0.05) in the positive rates between the diagnoses of laparoscopy and those three laboratory tests. Conclusion: CA125, laparoscopy, T-SPOT.TB test, and ESR had a stronger diagnostic power for TBP, and they are reliable alternatives for the diagnosis of TBP.