Summary: Tuberculosis (TB), caused by the Mycobacterium tuberculosis complex (MTBC), poses a major global threat to the health of humans and animals. The Suidae family is highly susceptible to TB and is used as screening sentinels for testing the presence of MTBC in the environment, but swine TB (STB) tends to be neglected worldwide. China has the largest pig population in the world, but epidemiological information on STB is scarce. In this study, 1379 serum samples were randomly collected from 45 herds of Gansu province, China from February to June 2021 and tested with PPD-B-ELISA. The STB prevalence at individual level was 0.22% (95% CI: 0.04%, 0.63%) and varied from 0.00% to 2.20% in different cities. The prevalence at herd level was 4.44% (95% CI: 0.54%, 15.15%) and varied from 0.00% to 33.33% in different cities. The STB prevalence in intensively raised three-crossbred pigs (0.23%, 95% CI: 0.05%, 0.68%) was higher than that in free-range raised Tibetan pigs (0.00%, 95% CI: 0.00%, 3.85%) ( p = 0.81). Besides, 180 serum samples were collected from Guangxi province, China, and STB prevalence in Guangxi province (1.67%, 95% CI: 0.35%, 4.79%) was significantly higher than that in Gansu province ( p < 0.05). These latest STB prevalence data are strongly suggested to conduct a randomized nationwide cross-sectional study on a regular basis for the development of an effective national program for STB surveillance and control.