Raw waste water (RWW) from food industry is rich of organic matter and mineral nutrients, particularly,K and to lesser extents N then P. Such richness is attributed to the nature of some substrates involved inthe food processing e.g. molace of sugar beet or sugar cane. These two crops are known to require highamount of K and, thus, to further enrichment of their derivatives with that nutrient. As cost of K fertilizersis relatively high, this experiment was conducted to study the effect of applying RWW on soil fertility, yieldquantity and quality of greenhouse cucumber and tomato. Uniform 30-day old cucumber seedlings and45-day old tomato seedlings were transplanted to two multi-span greenhouses (1000 m2) on December12, 2012, at Dair Alla Research Station in Central Jordan Valley (JV). The transplanted seedlings weresubjected to 5 RWW treatments of 75% of the traditional amount of K fertilizer farmers of the JV applyduring the growing season, 100% of K of the traditional amount of K-fertilizer of which 25% were appliedbefore transplanting and 75% were applied during the growing season, 125% of the traditional amountof K-fertilizer where 25% were added to the soil before transplanting and 100% were added during thegrowing season, traditional amounts of N, P and K chemical fertilizers, and traditional amounts of Nand P chemical fertilizers only. The results showed that RWW can effectively substitute K-chemicalfertilizer and can also improve some soil fertility parameters by the end of the growing season. Forexample, increases in available K and organic matter in the RWW treated cucumber beds were 25–71%and 2–11%, respectively. Similar increases were reported in the case of tomato beds (7–62% and 7–17%).Such increases corresponded to increases in K uptake by cucumber and tomato plants (30 and 37%,respectively). Calcium uptake was also increased to levels as high as 40 and 34% in both crop cases.Results of this study indicated that the application of Raw Waste Water from Food Industry improvecucumber and tomato performance and soil fertility.