Michael Anthony Williams, who plays Union Cane, was a real-life boxer, just as was Tommy Morrison (who plays Tommy Gunn). He and Morrison were to have an actual match about a month after Rocky V was released, but it had to be canceled when Williams was hurt. The match was being hyped as "The Real Cane vs. Gunn Match".
Jodi Letizia, who played street kid Marie in Rocky, was supposed to reprise her role in this film. Her character was shown to have ended up as Rocky predicted she would: a prostitute, who had recently been made homeless. The scene however, ended up on the cutting room floor, although Letizia can briefly be seen during the street-fight at the end of the film. The character would be reintroduced properly in Rocky Balboa, where she would be played by Geraldine Hughes.
The character George Washington Duke is based on real life boxing promoter Don King; the character even uses Don King's catchphrase of "Only in America".
The golden glove necklace featured so prominently in this film was first seen in Rocky III, then again throughout Rocky IV. As a promotional gimmick, replicas of the necklace were distributed to moviegoers at the Hollywood premiere of Rocky V at Grauman's Chinese Theatre.
The speech Mickey gives to Rocky in the flashback sequence is based on an interview with Cus D'Amato given in 1985, shortly after Mike Tyson's first professional victory.
Originally, the scene where Rocky is knocked out, during his fight with Tommy Gunn, had Rocky remembering the fight with Clubber Lang and afterward, he sees Mickey as a hallucination on top of the subway tracks telling him not to give up. Ths scene didn't make the final cut.
Tommy Gunn's first fight in the film takes place in the same hall where Rocky fights Spider Rico in the opening scene of Rocky. Even the design of the opening shot of the scene is copied directly from the earlier film.
When George Washington Duke is introducing the fighters before the Tommy Gunn-Union Cane match, the man standing to Gunn's left is actual boxing trainer Kevin Rooney.
Sylvester Stallone originally toyed with the idea of killing Rocky off at the end of the film. The plan was that Rocky would die in an ambulance on its way to the hospital with Adrian by his side. At the hospital, she would have announced to the world of his passing and his spirit would live on with a final flashback of the famous scene of him running up the steps. Stallone ultimately abandoned this concept and rewrote the ending.
According to director John G. Avildsen, when shooting the picture, he felt that cinematographer Steven Poster was over-lighting many of the scenes, and thus negating the realism of the piece. He told Poster he wanted the film to look more like Rocky, which had been lit by James Crabe, oftentimes using a single spotlight to light an entire scene (such as the opening boxing match). Poster told Avildsen that the original film "looked like a cheap documentary". Avildsen responded to this piece of criticism by smiling and saying, "Exactly".
Just as he had done with the first four films, writer Sylvester Stallone incorporated much biographical material into the plot of the film. Stallone particularly focused on the notion of Rocky's fall from grace. In Rocky III and Rocky IV, Rocky was top of the world, unbeatable and incredibly famous and popular. These two films had coincided with the height of Stallone's own popularity, which had waned decidedly in the years since Rocky IV. As such, when composing the script for Rocky V, he decided to look at the notion of how a man can have it all, only to suddenly lose it.
Gonna Fly Now is not sung in this movie, it only appears in an instrumental form played by the band when Rocky arrives back in the States at the beginning of the movie. This is also the last film in the series NOT to include a version of the song with lyrics, as the "traditional" sung version returns in Rocky Balboa.
This is the first movie where Rocky's real name, Robert, is used. When Rocky first meets Tommy Gunn, as George Washington Duke pulls up in his limo, Duke says "Mr. Robert 'Rocky' Balboa!"
According to director, John G. Avildsen, Rocky was originally going to die after the street fight with Tommy Gunn. However, they were ordered by the studio to change the ending, because they told him iconic characters like Rocky Balboa shouldn't die.