H azardous and Toxic Material Waste is the residue from a business and/or activity containing hazardous and toxic substances. One of the important components for Hazardous and Toxic Material Waste management is the presence of Hazardous and Toxic Waste Temporary Storage Facility. The objective of this planning is to identify the sources and types of B3 waste at Campus A, Trisakti University, and to plan the design of the Hazardous and Toxic Waste Temporary Storage Facility at Campus A, Trisakti University. Campus A, Trisakti University, has eight locations as sources of Hazardous and Toxic Waste, reclassified into two based on their activity sources, namely office Hazardous and Toxic Waste and laboratory Hazardous and Toxic Waste. Data on office Hazardous and Toxic Waste at Campus A are placed in a temporary storage container in the form of a cardboard box. Data sampling for liquid Hazardous and Toxic Waste and solid Hazardous and Toxic Waste from laboratories is obtained through calculating the Hazardous and Toxic Waste generation data produced by laboratories over eight days. Office Hazardous and Toxic Waste is classified into four categories of Hazardous and Toxic Waste types, and laboratories produce six types of Hazardous and Toxic Waste. The generation of office Hazardous and Toxic Waste for 30 days is 74,775 kg, for 90 days is 224,325 kg, and for 365 days is 909,762 kg. The generation of liquid Hazardous and Toxic Waste from Campus A laboratories for 30 days is 266.08 L, for 90 days is 798.24 L, and for one year is 3,237.33 L. The total Hazardous and Toxic Waste generated by Campus A, Trisakti University, for one year is 4.15 m3/year. The planned Hazardous and Toxic Waste Temporary Storage Facility building has a length of 10.75 m, a width of 8.25 m, and a total height of 7 m.