On a resume, a blank QR: definitely not. You're essentially saying "If you want to know more you have to go elsewhere, and I'm not telling you what's there". So you're asking the other to judge the relevance of the QR code and do more work. If your resume is good there's no reason to add the QR code.
On a resume, a well-described QR, saying something like "A portfolio of my latest work can be found here": maybe. If it's not essential information but you're offering it to satisfy the curiosity of the reader, it's OK. If they don't visit the site they should not miss any relevant information. And 'well-described' includes the full URL written out below the QR so that they know here it will take them.
On a business card, yes. There's not much space on the card. But again, the essentials that you did communicate before the existence of QR codes should remain on the card.