A sludge treatment system, comprising a pump (1), an ozone generation device, an ejector (2) and pipe reactors (3). The pump (1), the ozone generation device, the ejector (2) and the pipe reactors (3) are sequentially connected by pipes. An oxygen generator (4) and an ozone machine (5) are arranged within the ozone generation device, and are connected by a pipe. The ozone generation device is used for providing ozone into the pipe reactors (3). The inner surfaces of the pipe reactors (3) are coated with a catalyst layer used for increasing the oxidative capacity of the ozone on the sludge. Spiral fin plates (6) allowing a fluid to generate a spiral flow are arranged within the pipe reactors (3). Also disclosed is a sludge treatment method using the present sludge treatment system. The present system has a high ozone utilization rate, and a low ozone input proportion.