 Rhodococcus erythropolis and acidithiobacillus ferrooxidens were identified as the most effective bacteria in removing sulfur compounds from crude oil. These bacteria were able to achieve a maximum desulphurization efficiency of 47%. Additionally, the use of PTCC105 medium resulted in a maximum desulphurization efficiency of 19.74%, while the use of SFM and PTCC105 achieved a combined desulphurization efficiency of 47%. Furthermore, the optimal operating conditions for the biodegradation process included a mixing speed of 180 rpm, a temperature of 35 degrees Celsius, a surfactant dose of 0.05%, an OWR of 0.25, and an acidity of 0.5. This article was authored by Wism Mohamed Karim Al-Kazali and Sayyid Ahmad At-Tai.