[Objective] The improvement effects of chicken manure and slag addition on dredged soil were investigated in order to provide a theoretical basis for resource utilization of dredged lake soil. [Methods] A pot experiment was conducted with dredged soil as the test soil and Pennisetum hydridum as the planted species. Four treatments were established: control (CK, no additions of chicken manure and slag), addition of 5% chicken manure (T₁), 5% chicken manure + 5% slag (T₂), and 5% chicken manure + 10% slag (T₃). The effects of the different treatments on the physicochemical properties of the dredged soil, and on the growth and nutrient uptake of Pennisetum hydridum were analyzed. [Results] All three treatments significantly improved the physicochemical properties of the dredged soil compared with CK. T₃ had significantly lower bulk density and higher total porosity and capillary water holding capacity than the other treatments. Soil organic matter, total nitrogen, total phosphorus, total potassium, alkaline hydrolysis nitrogen, available phosphorus, and available potassium content were all at the highest levels with T₃. The chicken manure and slag additions significantly increased the growth and nutrient accumulation of Pennisetum hydridum, with the T₃ treatment showing significantly greater plant height, biomass, and accumulation of nitrogen, phosphorus, and potassium in aboveground and belowground plant tissues than observed for the other treatments. The results of the comprehensive evaluation by principal component analysis showed that the capacity of the three treatments to improve dredged soil followed the order of T₃＞T₂＞T₁. [Conclusion] The addition of chicken manure or chicken manure + slag significantly improved the physicochemical properties of the dredged soil and promoted the growth and nutrient accumulation of Pennisetum hydridum, and the T₃ treatment had the greatest capacity to improve dredged soil.