Pakistan is primarily an agricultural nation. Agriculture is the backbone of our economy, and it accounts for around 19.3 percent of our total gross domestic product. Pakistan ranks among the world's top 10 producers of wheat, maize, rice, cotton, and sugarcane, according to the United Nations Food and Agriculture Organization. It also cultivates edible oil seed crops. Water is the most important parameter of which we use for the cultivation of various crops. Pakistan is a country where irrigation water is extremely valuable. Irrigation schedule affects a crop's agronomic and economic viability. For the sake of water conservation as well as enhanced crop yields, it is essential. Based on monitoring soil water levels and crop water requirements, irrigation scheduling can be used to apply water for cultivation in accordance with predefined schedules. How much water to be apply when to a particular crop depends heavily on the kind of soil and weather circumstances this is an important practical component of irrigation. Crop water requirements and crop coefficients are the most significant parameters that must be determined precisely at local levels to determine how much water is required for crop growth at various stages. There are many approaches for determining crop water requirements, but Lysimeters is the most effective. Lysimeters are devices that are routinely used to determine agricultural water requirements all around the world. The water required by different crops like wheat, oat, carrot, and maize at different crop growth stages was determined using non-weighing type lysimeters in this study. To compute the crop coefficient, the Penman–Monteith equation was used, which takes into account daily mean temperature, wind speed, humidity, and solar radiation as inputs to the equation. Reference values for evapotranspiration during this period are taken from the metrology station. The water requirement of wheat crop of variety Fakhre Bhakhar and Anaj-17 are 328.4mm and their crop coefficients or kc values were in between 0.49 to 0.81. The water required by carrot crop 54mm and its crop coefficients taken out from the study are in between 0.78 to 0.94. Water requirement of maize crop for hybrid variety was found to be 362.6mm and its crop coefficients were in between 0.22 to 1.44. Water required by oat crop throughout its season with including three time harvesting is 303.4mm and its crop coefficient is 0.29 to 0.81. Water requirements of each crop and crop coefficients calculated by this study are close enough to recommend by FAO.