Paintings, drawings, photos, poetry and films are on show at the at 15 Barkers Pool - opposite the City Hall - with free entry, 10am to 6pm.
It was due to end on Friday but due to public demand has now been extended to Thursday, August 1.
Presented by charity Style For Soldiers, which provides clothing for injured military personnel, Art In The Aftermath is one of several events in the city featured alongside the Invictus Trials - where wounded and sick ex-servicemen and women are competing for the right to represent the UK at The Invictus Games in The Hague, Netherlands, in 2020.
The exhibition highlights how creative arts is also helping injured squaddies now battling with PTSD and physical life changing injuries whilst celebrating exceptional talent.
Many of the artists are in residence throughout the week.
Dougie Adams and Stewart Hill are both local to Sheffield and their paintings of the city and surrounding landscapes are on show.
Stewart and Karl Tearney will perform their poetry and talk about their work with daily audience Q&As, 1pm to 2pm.
Authors Harry Parker and Karl Tearney will also read from their books. Karl's first book of poetry, Second life, is on sale at Waterstones in Sheffield and he will be signing books all week at the exhibition.
Other artists on show include Martin Wade and John Cutting. All art work is on sale to the public. along with prints and books, with proceeds going direct to the artists.
Style for Soldiers was founded 10 years ago by menswear designer Emma Willis in response to casualties in Iraq and Afghanistan at the height of the conflict.
She visited patients at the Military Rehabilitation Hospital, measuring them for clothing as a gift of thanks for their bravery and sacrifice, to help with self esteem, confidence and to dress them for new careers.
Emma has since encouraged businesses like M&S, Russell & Bromley and Mr Porter to provide hundreds of suits, pairs of shoes and other clothing.
Significant long term support has been given by other companies including Christies, Barclays, Lock and Co Hatters, The Veterans Foundation, Burberry and Pol Roger.
The charity also provides bespoke regimental walking sticks which have been sponsored by Their Royal Highnesses The Prince of Wales and Duchess of Cornwall.
Art In The Aftermath came about with a first exhibition at London's La Galleria last November after Emma met several injured soldiers who have turned to art and poetry to help with the psychological healing process.
The charity has awarded seven arts sponsorships and each have resulted in the start of successful careers.
The Sheffield exhibition includes powerful images of Emma's visits to Headley Court Military Hospital, as well as photographic portraits of injured soldiers dressed in a Style for Soldiers and Mr Porter photo shoot by top fashion photographers Ben Weller and Boo George, to show the importance of smart clothes for morale and self confidence when transitioning into civilian life.
Ambassadors of the charity include Charles Dance, David Gandy and Telegraph Fashion Director Lisa Armstrong.
The exhibition also features several films by veterans including former Royal Engineer and triple amputee Matt Weston’s short film For Love of Words, starring Style for Soldiers Ambassador Charles Dance.
Emma owns her own boutique shirtmaker business in London's Jermyn Street - where her famous customers include HRH Prince Charles, actors Benedict Cumberbatch, Colin Firth and 007 star Daniel Craig.
She co-organised the Big Gig opening concert with Sheffield's Grammy Award winning Eliot Kennedy, to launch the Invictus Trials, at Sheffield FlyDSA Area on Monday night.
She said of the art exhibition: "We've a great variety of art. Abstract art, portraiture, sculpture, landscape, beautiful dogs, lovely poetry, poetry books. Also books written by soldiers of their experiences.
"John Cutting has created a most beautiful horse head, made out of horse shoes, held together with a strong, steel, central core."All the art is for sale. We have prints as well. Some very affordable and fabulous art and any sale will go directly to the artist. Prices start around £10 for a book and go up to £1,000 for a painting."
Also taking place in Sheffield this week during the Invictus Trials are performances of Soldier On, a heart-warming play about a group of ex-soldiers who become a company of actors, dealing with traumatic experiences, and what happens when you leave the military family. Last performance at Sheffield City Hall is Thursday, July 25, at 7.30pm. Tickets are available at the venue in person, visit www.sheffieldcityhall.co.uk or call 0114 2789 789
An Audience with Sir Michael Morpurgo, with the War Horse author chatting to paralympian Ade Adepitan, was at the City Hall on Wednesday afternoon.