The invention relates to a wastewater and sludge treatment technique, which particularly provides a sludge and wastewater free treatment system. The system comprises grilles, an aerated grit chamber, a hydrolysis acidification pond, an oxidation pond and a secondary sedimentation pond which are orderly connected, and the system also comprises a disinfection pond, a slag pond, a slag concentration tower and a sludge dewatering machine. When the system is operated, the wastewater passes through wide and narrow grilles to remove large impurities and enters the aerated grit chamber for sedimentation treatment, the discharged water enters the hydrolysis acidification pond; by a sludge bed in the hydrolysis acidification pond, the wastewater and reflux slag sludge are captured and the slag sludge is decomposed; the wastewater after the sedimentation treatment passes through a fixed type biological bed in the oxidation pond for biological treatment, the discharged water enters the secondary sedimentation pond for slag sedimentation, the discharged water after the slag sedimentation enters the disinfection pond for disinfection treatment, the water after the disinfection treatment can be discharged or reutilized, and the sedimentation slag is sent to the slag pond, and is concentrated by the slag concentration tower and is sent to the sludge dewatering machine for dewatering treatment. The sludge and wastewater free treatment system has the advantages of low equipment investment, low operating cost and good effect of wastewater treatment.