Objective: To explore anthelmintic effects of oral administration of aqueous extract of Sauce llorón(Salix babylonica; SB) against gastrointestinal nematodes and Moniezia spp. Methods: Sixteen Pelibuey male lambs of 3-4 months of age and(23.7±3.3) kg body weight were used in a completely randomized design to be fed a total mixed ration(Control; SB0), or Control plus SB extract using 20(SB20), 40(SB40) and 60(SB60) mL/lamb/day for 45 days. Lambs had a natural gastrointestinal nematodes and Moniezia spp. infection and had never been treated with chemical anthelmintic drugs. Individual faecal samples were collected for ova counting using Mc Master procedure after 0, 7, 14, 21, 30 and 45 days post extract administration. Results: No extract dose×day interactions for both gastrointestinal nematodes and Monieziaspp. egg count were found. Administration of SB extract had a higher effect(quadratic effect, P=0.0064) at dose of 20 mL SB/lamb/day for gastrointestinal nematode eggs during the first 21 days; however, the dose of SB40 tended(linear effect, P=0.0897) to be more effective than the others for Moniezia spp. egg during the first 7 days. Sampling day had a linear(P=0.0436) effect on Moniezia spp. egg count. Conclusions: The aqueous extract of SB could be more effective against nematodes at 20 and at 40 mL/lamb/day for Moniezia spp. The use of the SB extract could represent a promising alternative to synthetic anthelmintics for the treatment of gastrointestinal nematodes and Moniezia spp. in small ruminants from organic and conventional production systems. Objective: To explore anthelmintic effects of oral administration of aqueous extract of Sauce llorón (Salix babylonica; SB) against gastrointestinal nematodes and Moniezia spp. Methods: Sixteen Pelibuey male lambs of 3-4 months of age and (23.7 ± 3.3) kg body weight were used in a completely randomized design to be fed a total mixed ration (Control; SB0), or Control plus SB extract using 20 (SB20), 40 (SB40) and 60 (SB60) mL / lamb / day for 45 days. had a natural gastrointestinal nematodes and Moniezia spp. infection and had never been treated with chemical anthelmintic drugs. infection and had never been treated with chemical anthelmintic drugs. Individual faecal samples were collected for ova counting using Mc Master procedure after 0, 7, 14, 21, 30 and 45 days post extract administration. : No extract dose × day interactions for both gastrointestinal nematodes and Monieziaspp. Egg count were found. Administration of SB extract had a higher effect (quadratic effect, P = 0.0064) at dose of 20 mL SB / lamb / day for gastrointestinal nematode eggs during the f irst 21 days; however, the dose of SB40 tended (linear effect, P = 0.0897) to be more effective than the others for Moniezia spp. egg during the first 7 days. Sampling day had a linear (P = 0.0436) effect on Moniezia spp. egg count. Conclusions: The aqueous extract of SB could be more effective against nematodes at 20 and at 40 mL / lamb / day for Moniezia spp. The use of the SB extract could represent a promising alternative to synthetic anthelmintics for the treatment of gastrointestinal nematodes and Moniezia spp. in small ruminants from organic and conventional production systems.