The singer, who was to sing 'Kiss It Better' from her recent release Anti at the 58th annual awards ceremony, has been advised to give her vocals rest for 48 hours, Billboard reported quoting her representative.
The 27-year-old star tweeted an apology to her fans, famously called "Navy", on micro-blogging site Twitter.
"#NAVY so sorry I couldn't be there... Thanks Grammys and CBS for your support tonight."
The singer was "at risk of hemorrhaging her vocal cords," the rep said, adding she had been taking antibiotics for three days, though the meds "did not kill the infection adequately."