If they are EF lenses (which they are), then they will be compatible. However, if the digital camera is anything but full-frame, your lenses' length will be multiplied by a factor of 1.6x (e.g., a 400mm lens will be equivalent to 640mm). If it is the EOS-1D series, it will be a factor of 1.3 (400mm = 520mm).
I have an Canon EOS 620 35mm camera and want to move to digital. However I have a number of lenses as well. Are these lenses compatible with the Canon digital SLR line?