Urea and inhibitors are weighed and mixed with each other to make different combinations and applied in a solution form. A combination of two inhibitors including ammonium thiosulphate (ATS) and 2-chloro-6-(trichloromethyl) pyridine (nitrapyrin) were prepared with different ratio of 1:1, 0.25:0.75, and 0.75:0.25, which named as A1, A2, and A3, respectively. 100 mL solution of each combination was prepared by dissolving 0.21, 0.51, and 0.90 g of inhibitors into 2.34 g of a fixed quantity of urea with the addition of water to get the desired volume to make 0.10, 0.25, and 0.50% combinations, respectively. After sowing rice crop into the pots, these prepared combinations of urease inhibitors such as 0.10, 0.25, and 0.50% were applied in the soil of all three districts. Alone urea was used as a control to compare the results. After the application of urease inhibitor with urea, the readings were taken with the difference of one day in a consecutive manner up to 36 days to check the hydrolysis of urea .