The discovery that certain microorganisms, living within a marine environment, can actually degrade components of oil, has made possible the utilization of biological methods for the treatment of oil spills. A biosurfactant accelerates the process of degradation of pollutant composites. The objective of this work was to study the bioremediation in situ of a diesel oil spill by utilizing a biosurfactant produced through fermentation and then compare it with chemical remediation. The quantification and identification of hydrocarbons were carried out by the process of gas chromatography. The soil indigenous microorganisms were monitored. The experiment with biosurfactant reached reductions of 99% of the aliphatic hydrocarbons, while that of the chemical disperser experiment reached a maximum of 90% reduction in 180 days. In 15 days the biosurfactant removed 77% of the aliphatic hydrocarbons, the diesel oil experiment 8.7% and the chemical disperser only 5%. The biosurfactant was 99% effective for the removal of aromatic polycyclic hydrocarbons, up to 3 rings.