The invention discloses a chlorinated exhaust gas treatment system and process. The system includes a first TiCl4 washer, a first TiCl4 gas liquid separator and a second TiCl4 gas liquid separator arranged in parallel, a second TiCl4 washer, a first hydrochloric acid gas liquid separator, a first hydrochloric acid washing tower, a second hydrochloric acid gas liquid separator, a second hydrochloric acid washing tower, a dechlorination tower gas liquid separator, a dechlorination tower, an exhaust gas water seal, an exhaust gas water seal gas liquid separator and a high-altitude discharge cylinder which are arranged in the exhaust gas flowing direction. The second hydrochloric acid washing tower is connected to the first hydrochloric acid washing tower through a pipeline, and the first hydrochloric acid washing tower is connected to the second TiCl4 washer and/or the first TiCl4 washer through the pipeline. The chlorinated exhaust gas treated by the system and process is free of harmfulgases such as titanium tetrachloride, HCl and residual chlorine and can be discharged in accordance with the standard. Wastewater resources are fully utilized, and environmental and economic benefitsare achieved.