In this trial, the effect of different levels of Echum amoneum (EA) (0.3, 30, 300 or 3000 µl) on in vitro ruminal fermentation characteristics and methane production was assessed. The parameters studied were in vitro Gas Production (IVGP), methane production, ammonia (NH3-N) concentration, in vitro Organic Matter Degradability (IVOMDe), Partitioning Factor (PF) (the ratio of substrate truly degraded to gas volume produced at 24 h of incubation) and total Volatile Fatty Acids (VFAs) concentration. The correlation of methane gas with total protozoa population and three subfamilies of Entodiniinae, Ophryscolecinae, Diplodiniinae and family of Isotrichdae, also, were studied. Gas production from insoluble fraction (b) (linear effect; P<0.01) was significantly (quadratic effect; P<0.01) increased with increasing level of EA. The inclusion of EA at either 300 or 3000µl increased IVGP at hours 24 and 54 (linear effect; P<0.01). However, methane production was reduced (linear effect; P<0.05) by 54, 41 or 43% when EA was added at 3, 30 or 300 µl respectively, without changing the degradability of organic matter. The inclusion of EA extract reduced NH3-N concentration (P<0.01), while PF (quadratic effect; P<0.01) led to an increase. On the other hand, EA addition decreased the concentration of VFAs and acetic acid (P<0.05), but increased the propionic acid (P<0.05). Moreover, the inclusion of EA has shown a significant effect of antiprotozoal activity, and, there is a tendency of total protozoa population, Diplodiniinae, Ophryscolecinae, and Isotrichdae family to decline. The results finally suggest that EA plant is of the potential to positively manipulate in vitro ruminal fermentation.