Not on its own. The only way to lose weight is to burn off more calories than you take in.

yeah alott...I'VE done it...but you should do diet too so you'll loose more weight

Well, yes. It isn't a magic bullet. Drinking water does a couple of things. It hydrates your body which in turn helps it flush excesses out of your body. It also helps your stomach to not feel hungry. Lemon adds flavor which - depending on where you live - makes the water taste better. Lemon is a citrus fruit - like grapefruit, orange and lime - eating those fruits regularly helps your body to burn fat.
Be aware that you can't live on "water with lemon". A balanced diet, regular meals and a little exercise is the best diet.

nope - but of course it's really good for you and the water does help fill you up so you eat less and the lemon does serve as a sort of internal astrigent helping to cleanse your system a bit :)

its worth a shot because lemmons have more acid in them then grapefruits so they will most likely burn more fat

nope dont think so .. nothing in the lemon helps loosing weight

That's what I've always heard...
But there are lots of benefits, really...
(see below)

I have heard alot of things. Lemon gives it a flavor therefore somewhat curbing your diet and acts as a diuretic (makes you urinate). Plus drinking that is better than drinking soda...