This research work presents the effects of dyeing wastewater on the quality of concrete. Dyeing wastewater from Marina area, Sokoto town, was used in the study. The setting time of cement paste mixed with dyeing wastewater, the chemical composition of dyeing wastewater, and the workability of grade 20 concrete made with wastewater and portable water, were tested. The compressive strength of grade 20 concrete at different ages of curing was tested after the cubes were cast and cured in both dyeing wastewater and portable water. The results showed that, the workability of concrete made with dyeing wastewater is lower than that of concrete made with portable water and, there is a significant effect on water type on the strength of concrete produced. The compressive strength of concrete made with dyeing waste water decreased with age of curing, and the 28 days strength fell lower than the designed strength, while the compressive strength of concrete made with portable water increased with age. It was therefore concluded that the dyeing wastewater should not be used for mixing and curing of concrete.