A study of pesticides in the Bizerte lagoon watershed on the Mediterranean coast of Tunisia showed that herbicides and fungicides are the most commonly used compounds. A survey was made of selected farmers. Pesticide contamination was monitored in the water column and sediments at four selected sampling sites (lagoon (A) and in three oueds-Chegui (B), Garaa (C), and Tinja (D)). Polar organic chemical integrative samplers (POCIS) were used to assess pesticide contamination. Thirty-two pesticides were investigated; the total concentration of active ingredients ranged from 35.9ngL-1 in Tinja oued to 1246ngL-1 in Chegui oued. In the lagoon, the total concentration of pesticides was 67.7ngL-1. In the sediments, the highest concentration was measured in Chegui oued in the spring (31ngg-1 dw). The main compounds found in the analyzed sediments were prosulfocarb and tebuconazole molecules.