Is there fake money in Vietnam? If yes, how can I distinguish the real one from the fake one?

Yes, just like any other kind of monies, there is fake money in Vietnam. Our government is cracking down on it, but you still need to be aware of this, especially when you try to buy things from those street vendors or you change money from black market

As Vietnam Dong is made of plastic  (Like AUD$ or Sing$, some small notes like: 5 thousand, 10 thousand or 20 thousand some time could be found in both plastic and paper) and for the ways to identify fake money are by the color, the watermark, the plastic paper, and the blur image of Ho Chi Minh:

The plastic of VND notes is hard to imitate and very durable and fake money are usually breakable, that is, the images and colors are not so sharp.

On Vietnamese Dong (plastic money) the color on counterfeit money is also not clear. On real bills there are always two images of Ho Chi Minh: One clear and one blur, and there is a section that we can see through the plastic money with the number of the bill on it (This part is very easy to find down if the money is fake or not)