Written and first recorded by Paul Anka (1970).
Hit version by Tom Jones (US #2/R&B #42/UK #13 1971).
Also recorded by Paul Anka & Tom Jones (2013).
From the wiki: “‘She’s a Lady’ was written by Paul Anka, and was first on his album Paul Anka ’70s.
“‘She’s a Lady’ was most-famously performed by Tom Jones, becoming his highest-charting single to date in the US. The song was re-released in 2013 on Paul Anka’s Duets CD with a new recording featuring both Anka and Tom Jones.”
Tom Jones, “She’s a Lady” (1971):
Tom Jones, “She’s a Lady” live performance (1974):
https://youtu.be/hpsGh4Amt44
Paul Anka & Tom Jones, “She’s a Lady” (2013):