Purple sweet potato contains many active components such as anthocyanins and flavonoids that can act as an antioxidant and antimicrobial, but research on the antimicrobial activity of purple sweet potato has not been much studied. This research aimed to examine the characteristics of purple sweet potato tuber extract as antimicrobial compounds. Purple sweet potato was extracted by two different solvents which were ethanol and ethyl acetic at 25oC and 40oC for 1 - 6 hours. Each extract was tested its antimicrobial activity againts Bacillus cereus, Staphylococcus aureus, Escherichia coli, Enterobacter, Aspergillus niger, and Mucor sp. using agar diffusion method. The result showed that the combination of etahol – ethyl acetic (80:20) could inhibit B. cereus, S. aureus, E. coli, Enterobacter with the inhibition zone of (9,10 – 10,50 mm), (7,70 – 8,40 mm), (7,10 – 8,10 mm), and (5,60 – 6,60 mm) respectively. However it did not give any inhibition to A. Niger and Mucor sp. The spore of B. cereus were more resistant to the extracts than the vegetative cells showed by the inhibition zone of 6.33 for the first and 9.89 mm for the later. Protoplasts and sferoplast had much greater diameter inhibition than the undamaged bacterial’s membrane cell. The extracts more stronger than penicilin G to inhibit bacteria and equivalent to streptomycin at the concentration of 10 to 50 ppm. The cell leakage test conducted by AAS showed that the amount of Ca+ ions leakaged from Gram negative bacteria was greater than that the one from Gram positive bacteria and conversely the number of K+ions leakaged from Gram potive bacteria was greater than that the one from Gram negative bacteria. The morphology observation by using Scanning Electron Microscope (SEM) observation indicated that the extract has caused cell wall damage.