There are many mixed answers. But they're all answers from a few years ago and relating to Polymer 1.
Thanks.
It does work but it won´t work well. Have a look this. The only way jquery and polymer work well togehter is polymer 1 and shady dom but thats deprecated.
The question can be interpreted in two ways - can legacy jquery code create polymer components/custom tags?
The answer is YES.
The other interpretation is - can I use jquery INSIDE my web components?
The answer is "maybe, but its a really bad idea, don't do it".
来源：https://stackoverflow.com/questions/45338428/does-jquery-work-well-with-polymer-2