Abstract: Filariasis was distributed in the eastern, north-eastern and south-eastern parts of Guizhou Province, where the disease was prevalent in 47 out of 87 counties, 21 with bancroftian filariasis, 25 with malayan and 1 with mixed infections, the microfilaria rates being 0.06-24.2% before control. It was estimated that the number of filariasis patients was more than 1 million. Among them, about 40% had clinical symptoms and signs including lymphangitis, lymphadenitis, funiculo-epididymitis, elephantiasis, hydrocele, chyluria etc. and the others had microfilaraemia only.Large scale control project of filariasis was carried out from 1958 to 1984 in Guizhou province including mass surveys and integrated control measures. Up to 1984, 16, 632, 958 people were blood-examined and 13,365,095 persons were treated in 47 endemic counties of the province. Based on several years of field experience, it was decided to use repeated mass blood surveys and selective treatment with hetrazan (DEC) in low endemic areas, while in moderate and high endemic areas, it was recommended to use repeated blood surveys and mass treatment with DEC or DEC-medicated salt for the whole population aged over 5 years. In addition, in malayan filariasis endemic areas where the main vector was Anopheles lesteri anthropophagus, the control measures included vector control by indoor residual spraying of insecticides. The average microfilaria rate was thus reduced from 9.86% before control measures were taken to 0.17%. Survillance and long-term measures are being considered.