Power supply (pc build)

Solution
Most PSUs are made in China, or one of the other Pacific-Rim countries. So... yes. Depending on the make model PSU you are considering.
Make & model is more important than where it's made.

Whilst there are some poor-quality, rubbish PSUs coming out of China, they also assemble them for reputable manufacturers from parts shipped in to China from neighbouring countries. It's the way of the world these days - - - parts are high quality but labour is cheaper in China.