Missing Trailer Scene: The five and a half minutes long Hong Kong trailer for the second film is the only source to see glimpses of some deleted scenes; Blood covered Kit being brutally beaten up, Kit seeing his wife while still having injuries from the beating on his face, Ken and Lung playing with the bird.
Old Shame: John Woo disowned A Better Tomorrow II, with the exception of the final gun battle.
This film became so popular, that kids in Hong Kong started wearing long coats, known as "dusters" to copy Mark.
Chow Yun-fat wore Alain Delon sunglasses in the movie. After the movie, Hong Kong was sold out of Alain Delon's sunglasses. Delon sent Chow a personal thank you note.
Star-Making Role: Chow Yun-fat as Mark Gor in the first film. Despite not actually being the main protagonist, his coolappearance and charismatic performance led to his breakout popularity, and would launch his Hong Kong film career.
The second film had this. John Woo and producer Tsui Hark disagreed on the focus of the film. Tsui felt that the film should focus more on Lung, while Woo's original version focused more on characters Ken and Kit. Hark also insisted that the film should be shortened to a commercially viable length, which in Hong Kong is considered under 120 minutes, so theatre owners could show the film at least eight times a day. Woo refused to cut the film down and when he and Hark couldn't agree about the focus of the film and how it should be re-edited, Hark went and started secretly re-editing the film himself, since he had equal control with the editing of the film along with three other editors (Woo being the fifth editor). At the same time when Hark would cut some parts out Woo would went and also secretly put the missing parts back in. With only a week remaining before movie was to be released in theaters, and with pressure from the studio and distributors to trim the film down, Woo and Hark agreed to send the movie to "Cinema City Editing Unit", which meant that they sent each reel of the film to one of Cinema City's editors, who would then go to work on his particular reel. There was no overall supervision whatsoever by either Woo or Hark. Each of these editors just cut things out as they saw fit, then they returned the reels. What they came up with is now the official released version of the film.
The film was also notorious for stunt mishaps. Chow Yun-fat was almost blown up when the explosion outside the mansion door being more powerful than expected. Some of his hair was singed, and he was blasted forward. The shot in the film is his real reaction. Director Ronny Yu was the stunt double in the warehouse scene. He wrenched his back after slipping on water puddle while carrying Dean Shek. Also the stuntman for Leslie Cheung who performed the speedboat jump landed incorrectly and broke his foot.
You Look Familiar: In addition to Chow Yun-fat playing his own twin brother in A Better Tomorrow II, Shing Fui-on plays a different heavy in both films.