Coastal regions are areas or environments that receive large amounts of organic pollutants. Thus, sediments in these areas have high concentrations of organic matter, which can compromise the health of the population and cause risks to the ecosystem. This work aims to determine the levels of aliphatic hydrocarbons and isoprenoids (pristane and phytane), estimating the sources of release on beaches on the west coast of Ceará. Surface sediment samples were collected at low tide and stored in metal containers, and kept under refrigeration until the Environmental Studies Laboratory (LEA-UFC). Sediment extracts were obtained through ultrasound-assisted extraction methodology followed by a clean-up step to remove interferents. The extracts (apolar fraction) were analyzed by gas chromatography coupled to a flame ionization detector (GC-FID). Analytes were quantified by the internal standard method. The characterization of the sediment matrix was performed according to the parameters: Granulometry, %CaCO3 and %Organic Carbon (%OC), with values between 95.8% - 98.9% of sand, 1.61% - 7.49% and 0.1264 - 0.4573%, respectively. The sum of the concentration of the n-alkane series from n-C8 to n-C34 ranged to 2.74 - 4.69 ug.g-1 (mean=3.82 ug.g-1). Diagnostic ratios such as Prist/nC17, Phit/nC18, Prist/Phit, TAR and CPI were used to evaluate the origin of sedimentary organic matter from the coastal zone of Icaraí, Tabuba and Cumbuco beaches. A predominance of short-chain n-alkanes (n-C12, n-C14 and n-C16) was observed, with the exception of point 2, where there is no significant concentration of n-C12. According to VOLKMAN 1988 indicating an input of marine organic matter (phytoplankton). The TAR ratios indicate a predominance of a marine hydrocarbon in the study area. In contrast, at points 2 and 3 the CPI points to a predominance of anthropogenic activities. These levels may be associated with urban runoff, as well as local shoreline containment works. Values obtained for Pris/Fit ratios (~1), Pris/n-C17 and Fit/n-C18 (<1) suggest an input of petrogenic sources (oil) in early stages of degradation in the environment.