Hydroponics has been gaining increasing interest because of its contribution to reducing environmental impacts through minimal use of water and fertilizers. The objective of this work was to evaluate the production of arugula cultivars in the harsh region of Paraíba , under hydroponic system and under different plant densities and nutrient solution concentration. The research was carried out in Campus II of the UEPB (Lagoa Seca-PB) and followed a randomized block design in the 2 x 2 x 2 factorial scheme, two cultivars of cultivated arugula (Cultivated, Broad Leaf), two plant densities (10 and 15 plants per phenolic foam) and two concentrations of the nutrient solution (100 and 120%) with four replicates. The hydroponic system used was the NFT. For the nutrient solution, a commercial fertilizer produced for leafy olives (Compound + Calcium + Iron) was used. The seedlings were produced in phenolic foam (2 x 2 x 2 cm). The cultivation beds had 8 channels (4.5 m each), where each one represented one block. The spacing used was 0.25m x 0.25m between plants and between rows, respectively. The data of the variables were submitted to analysis of variance by the F test at 5% probability and the Tukey test to compare the means. At 41 days after sowing, the growth parameters were analyzed, where it was verified that the two arugula cultivars can be cultivated satisfactorily, in a hydroponic system, under the conditions of the harsh region of Paraíba without increasing the recommended dose of the nutrient solution and plant population.