A study on kinetics of anaerobic co-digestion of water hyacinth with poultry litter in different combinations was carried out in 250 ml batch digesters for 60 days retention period. Co-digestion was carried out in mesophilic temperature range of 30 to 37°C with a total solid concentration of 8% in each sample (fermentation slurry). The biogas was collected by the downward displacement of water and was subsequently measured. The observations show that water hyacinth when co-digested with poultry litter improved biogas yield significantly. The experimental data was tested for its fitness with Modified Gompertz equation. The kinetic parameters viz., biogas yield potential (P), the maximum biogas production rate (Rm) and the duration of lag phase () were estimated for each case using polymath software. The digester fed with 4gm water hyacinth, 18.87gm poultry litter and 77.13gm of water (PW3) produced maximum biogas of 0.39 l/gVS.