Upvote:1
I can't think of any reason why not, so long as you empty all the water out of it. People bring miscellaneous electrical appliances on airplanes all the time, and I don't see anything special about these.
If you want to make sure, you can ask TSA.
Upvote:2
With very few exceptions, the airlines do not care what you bring on the plane - as long as it fits within your carry-on allowance, and has made it past TSA, then the airlines will generally be fine with it.
The TSA "What Can I Bring?" website doesn't have anything for "humidifier", and whilst that doesn't give a definitive answer I'd say the chances of it not being allowed are zero - as long as there is no liquid in it at the time that you're trying to take it through security.
Technically as it's an electronic device larger than a cell phone you will need to remove it from your bag as you go through security - although as the electronics part is small you probably won't have an issue even if you don't.
Note that this is just discussing taking it on the plane - if your plan is to actually use it in flight that's a completely different story and would NOT be allowed by the airline.