Yes. You need to put a good amount of plumber's putty between the sink and the drain. Go to the hardware store and buy a small container of plumber's putty. Take out a pretty big piece. You should work it with your hands to warm it up (kind of like playing with silly putty). I make a long "worm" about 1/2" in diameter about 10" or so. Don't worry about using too much because any excess can easily be removed. Take your "worm" and press it around the drain piece that fits into the top of the sink. Push it into the drain hole and tighten from below. As you tighten it, the excess will ooze out. Once it's tight, just use your fingers to remove the excess, connect the drain pipe/trap. That should be it.
