The reuse of tertiary wastewater for crop irrigation presents itself as an alternative to the scarcity of quality water suffered by many countries in the Mediterranean region. Furthermore, this resource can provide an important saving of fertilizers as well as benefits to the environment, as it avoids the discharge of contaminated water into public waterways. This study focuses on the effect of irrigation with ozonized wastewater on the melon crop. In this study, melon crops were irrigated with either ozonized wastewater or ground water commonly used in the agricultural area (control treatment). Fertigation, by means of drip irrigation, was delivered according to the crop’s needs, evaluating the fertilizers contributed by each of the waters and that added in mineral form. Throughout the crop’s development, the characteristics of the water, soil and plant (leaf and fruit) were studied from a chemical, physicochemical and microbiological perspective. The results obtained show that irrigation with ozonized wastewater, in these conditions of crop growth, produces similar effects as ground water on the soil properties, on the concentration of macroelements in the leaf and fruit and on the yield of melon fruit. Furthermore, the reuse of this effluent leads to a greater saving in nitrogenous and potassium fertilizers compared to fertigation of the crop with ground water.