Abstract: Quality of irrigation water is an important ingredient of agriculture products and determinant of human health, the purpose of this study is to determine the mineral composition, physico-chemical parameters and water quality of opa water irrigation. Water samples were collected in 10 sterile capped 250 mL bottles and they were obtained from 10 different points around the opa water irrigation. Physico-chemical parameters such as electro-conductivity, total dissolve solid, pH and total solid, sodium percentage, sodium adsorption ratio, Kelly’s index and microbial analysis were also determined. The study revealed that the physico-chemical parameters of water samples, such as the electro-conductivity ranged from 2.3-2.7x100 ohm cm-1, total dissolve solid 47-153.6 mg L-1, pH ranged from 5.3-6.9, density and total solid ranged from 0.8386-1.010, 220-260 mg L-1, respectively. Major mineral elements in the water samples such as calcium, magnesium, sodium and potassium ranged from 12.7-16.2; 9.6-17.5; 28.9-50.1; 30.1- 32.5 mg L-1, respectively. Trace mineral element, such as Fe ranged from 3.5-5.4 mg L-1 and others including Zn, Mn, Cu, Pb, Ar, B were not available, respectively. It was concluded that the results of the physico-chemical parameters, major and trace mineral elements, sodium percentage, sodium adsorption ratio, Kelly’s index and microbial analysis that were obtained from the water samples were within the permissible limits and in line with World Health Organization guidelines.