Not today. No existing quantum computer comes close. But a powerful enough one could someday threaten the signatures that protect bitcoin, so developers are already working on upgrades.
Go deeperThe main risk is to coins whose public key is already visible on the blockchain, such as very old coins and addresses that have been reused. Draft proposals like BIP 360 (a new output type that hides the vulnerable key) and BIP 361 (a plan to phase out old signatures) are being discussed. Any change would need broad agreement before it activates.