Yes, but it is a non-selective herbicide. This means vinegar will kill or damage any green plant it touches, not just the weeds. It works by “burning” the moisture out of the leaves on contact. Using vinegar with 5% acidity will kill most small weeds, but it won’t kill roots of established perennials like dandelions. Horticultural vinegar with 20%-30% acidity is highly effective for eradicating tough weeds but it’s hazardous to skin and eyes and should always be used with extreme caution.