How to realize the harmless treatment and resource recovery of oily sludge is a major challenge in the field of petroleum production. Pyrolysis, as a method of thermochemical decomposition of organic matter in an anoxic environment, has great application potential in the harmless disposal and resource utilization of the oily sludge. Pyrolysis of oily sludge has become an important concern in the field of oil exploitation, refining and environmental protection, which has attracted intensive studies in recent years. In this paper, the latest achievements of the pyrolysis and process pollution control technology of oily sludge were reviewed. Guided by the new thermochemical technology of harmless disposal and recycling of the oily sludge, this paper comprehensively summarized and analyzed the recycling of oily sludge pyrolysis and process pollution control, aiming to reveal the transformation process and mechanism of oily sludge components conversion in the pyrolysis process, as well as the generation, transformation and migration routes of nitrogen and sulfur pollutants and their corresponding mechanisms. The design principles of catalysts and the optimization of reaction processes during catalytic pyrolysis and co-pyrolysis, the formation process and influencing factors of small organic compounds containing sulfur and nitrogen, and the migration and transformation of heavy metal elements were investigated. The future application prospect and development trend of this technology were prospected.