It is unknown whether quantum computing makes NP-complete problems easier to solve. There is a complexity class for problems that can be solved "efficiently" on using quantum computing, called BQP. How BQP and NP are related is unknown. In particular, if an NP-complete problem was shown to be solvable efficiently with Quantum Computing (and thus in BQP), this open (and hard) research question would be solved (or at least half of it).

Note that BQP is not "efficient" in a real-word fashion, but for theoretical study of Quantum computing, it's a good first guess