Haemonchis is a major health and welfare problem for small ruminants responsible for economic losses through reduced productivity and increased mortality. The in vitro efficacy of Callistemon rigidus was determined against Haemonchus contortus the most important parasite involved in this animal disease. Fresh eggs, infectives larvae (L3) and female’s adult were incubated at room temperature in aqueous and ethanolic extracts of C. rigidus for 24 h; 24 and 48h for effectivity assessment. The PBS used as negative control did not affect the involved developmental stages. Aqueous and ethanolic extracts induced 100 % mortality of female’s adults at 1 mg/mL with LC50 values of 0.067 ± 0.01 mg/mL and 0.067 ± 0.011 mg/mL respectively. The inhibition of eggs hatching rate varied from 12.33±2.08 % to 83.67±2.21 % with LC50 value of 0.351 ± 0.023 mg/mL. While the ethanolic extract inhibited 15.33±1.53% to 100±00% with LC50 value of 0.269 ± 0.005 mg/mL eggs hatching. The larval mortality rates increased from 62.5±9.57 % to 91.66±9.62% for aqueous extract with LC50 value 0.2±0.02 mg/mL and from 78.93±6.53% to 100±00% for ethanolic extract with a corresponding LC 50 value of 0.12±0.01mg/mL. Finaly, this study indicated that C. rigidus possess potential anthelmintic effect and further in vivo study is indispensable to validate its use as alternative anthelmintic against that GIN.