Katy Perry To Appear on “Tonight Show With Jay Leno” Show on June 21st! Posted by Grace | On 12 June,2012 | In General News, TV Katy Perry is scheduled to appear on Tonight Show With Jay Leno, aired on NBC on June 21, 2012. It was also rumored that Katy Perry will be appearing on “Jimmy Kimmel Show” by the end of June. The actual date is still remains unknown. Mrscassiefelton Please please please tell me the designer of your retro dress and shoes you are wearing on Jay Leno show.