I do not believe this superb little starter lens will fit the full-frame 5D, but I'm not positive. It was really designed for the APS-C-type-sensor cameras, such as the Rebel DSLR, and it is perfect for that purpose. Check with Canon to be sure. I have a 5D MkIII and I was considering this lens, too, but I think there is an issue with Canon's full-frame cameras. Probably a better choice would be 24-105 f/4 L. New "L" lenses are not inexpensive, but sometimes this lens can be found on internet bidding sites (such as eBay), and good deals can probably be found in that lens. It is fairly heavy with lots of glass, but it is superb and unsurpassed -- used by pros worldwide -- and coupled with the full-frame 5D, it doesn't get much better in digital photography. --Tom Tyson
Yes and no. Yes, it does "fit", but since all EF-S lenses were designed for crop body cameras it isn't compatible. EF-S lenses can only be used on 1.6 crop bodies, not full frame like the 5D or even on a 1.3 crop. I haven't tried it, but I think it would give new meaning to the term vignette.