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Over the last twenty years or so, the contamination of wastewaters and sludges by numerous organic or metallic micropollutants has been highlighted. The objective of this document is to characterize the quality of the different treated sludges in terms of micropollutants and to evaluate their evolution during different sludge treatment processes. For this purpose, at the Al-Hoceima (Morocco) wastewater treatment plant a number of micropollutants (n = 46) were monitored during sludge treatment including gravitational thickening, mechanical centrifugation, and chemical stabilization. Based on the quality of the treated sludge, a total of 33 compounds were detected in the treated sludge (in mg/kg DM - dry matter). In terms of treatment, thickening and stabilization does not have a significant impact on sludge contamination for metals and organic compounds, while some removal seems possible with centrifugation for several compounds. Three behaviors can be identified: no removal, a slight removal, and higher removal. Therefore, this allows a net elimination of micropollutants that could possibly be improved significantly by increasing the elimination through modifications of the operational parameters (retention time, temperature, pre-treatment, etc.).