Producer-Director-Writer Nasir Hussain was married to assistant choreographer Ayesha Khan but he was also romantically involved with heroine Asha Parekh, whose mother Sudha Parekh was her costume designer. All four worked together on this film, as well as Teesri Manzil (1966). In her 2017 memoir "The Hit Girl", Asha wrote that her mother was in denial about her romance with her married director. Eventually the romance ended, because Asha didn't want to be the other woman. None of the off-screen drama translated into any awkwardness on screen, since both films became major hits at the box office.
Aaj Kal Tere Mere Pyar Ke Charche was written for this film but was rejected by Dev Anand.
"Sally Tek Me Rum" song by Avi & The Supertones Band was a cover version of "Sau Saal Pehle".
When nasir hussein was making his debut as director with 'Tumsa Nahin Dekha' nasir saab wanted dev anand to be the hero of it, but dev refused and he told nasir saab that when nasir saab turned to producer, he will act in his film and when nasir saab started jpkhh, dev acted in it.
. re the Jab Pyar Kisise Hota Hai song "Bin dekhe aur bin pehchaane tum par hum qurbaan" was samples from Ron Goodwin's 'Dancing Eyes.