Abstract: Usage skills and parameters setting of Olympus CCD installed in JEM-2100TEM were narrated,which included adjusting the intensity of electron beam,adjusting the contrast and brightness of images;scaledisplaying and calibrating;properly acquiring image in SAED;observing samples and acquiring images in specialcases;protective setting of over-exposure;controlling the putting up and down of the fluorescent screen;restoringthe communication between CCD and TEM,etc.