This work presents the results of VOC’s emitted during the wastewater biosolids composting in two static piles. VOC’s were isolated by Solid Phase Microextraction (SPME) and analysed by Gas Chromatography/Mass Spectrometry (GC/MS). More than 150 organic compounds were identified including aliphatic and aromatic hydrocarbons, chlorinated compounds, ketones, mercaptans, sulfides, alcohols and amines, a must of them in concentration above the USEPA inhalation standards.