Abstract: The study was conducted to determine the prevalence of gastrointestinal nematodes of goats in Humbo Woreda of Wolaita zone from November, 2019 to March, 2020 and to investigate field efficacy of commonly used of anthelmintics against gastrointestinal nematode of naturally infected goats. A total of 384 goats were sampled for the presence of gastrointestinal nematodes and examined under microscope for the presence of nematode eggs and the number of eggs counted (quantified) using modified McMaster egg counting techniques. Out of 384 study animals, only 361 (94.0%) goats were found positive for nematode eggs of which 40 highly infected goats were used for the field efficacy trial and divided into four groups having 10 goats in each group. The first group was treated with albendazole, second with tetramisole, the third with ivermectin and the fourth were left untreated (as control). Faecal egg count reduction test was applied to determine the efficacy of anthelmintic at day 14 (post-treatment). Among anticipated risk factors, only the age, body condition and origin of goats showed statistically significant associations (p<0.05). The mean egg per gram of faeces at day 0 was >1300 for all treatment and control group while day 14 result nematodes for three treatment groups was 0. All the three anthelmintics tested revealed significant (p<0.05) reduction in nematode egg of goats at day 14. Faecal egg count reduction was 100% and same for all three treatment drugs. This study demonstrated that the prevalence of gastrointestinal nematode in goats was high thus, tested drugshad 100% efficacies against nematode of goats. In this regard, tested drugs can be used in the treatment of gastrointestinal nematode infections in goats.