Gaga was a huge fan of the London-born singer and paid tribute to Amy via Twitter to mark the sixth anniversary of her death on Sunday.
Above a photograph of Amy, Gaga wrote on the micro- blogging site, "We all miss you and your voice Amy. Good time to remember to treat people that we love with dignity and respect. What a talent. (sic)"
Amy died of alcohol poisoning back in 2011, aged 27.