Continuity mistake: When Forrest runs towards Jenny in the reflecting pond during the Anti-Vietnam Rally, he runs by the same man twice. Look carefully for the man in the top hat and you will see it is really the same shot from two different angles.
Factual error: Jenny shows Forrest a clipping of him in U.S.A Today (first published in September 1982), but on Jenny's grave it says she died on March 22 1982.
Revealing mistake: When Forrest finally catches shrimp on the boat, the net drops shrimp on the deck which are not only already dead, they're headless and very obviously processed for shipment to market.
Continuity mistake: In the scene where Forrest goes and visits Jenny (and is introduced to his son), there is an iron on the ironing board in the background. It stands up, then down, then up. The child's artwork in the background also disappears.
Factual error: During the 1972 New Year's Eve celebration, Forrest drinks a Dr. Pepper with a logo that wasn't devised until around the mid 80s.
Factual error: When Forrest and Lt. Dan first try catching shrimp on the new boat they catch a bunch of junk, including a Mello Yello can, which hadn't been invented yet.
Continuity mistake: In the scene where Forrest is getting on the school bus for his first day at school, he is standing at the door talking to Dorothy Harris, the bus driver. The shot from behind Forrest shows Dorothy's right hand on the gear shift knob. In the next shot, from inside the bus looking down at Forrest, her right hand is on the door-open lever. This shot changes several times, and each time her right hand is in those two different positions.
Factual error: In the scene where Forrest gets his discharge papers, he is practicing table tennis in a gym. The gym floor has a three-point line on the basketball court. It is a college or high school three point line- 19 feet, 9 inches. There was no three pointer in basketball at that time, especially at that distance.
Continuity mistake: When Forrest sees Jenny at the anti-war demonstration in Washington D.C. he runs through the crowd towards the pond. We see that the gap between the people who let him through closes immediately after him, but in the last shot it remains wide open, obviously to allow a more dramatic view of Jenny's and Forrest's reunion. However, when the crowd is shown from the other side there's no gap at all.
Factual error: Bubba says he was drafted into the Army, but his gravestone says he was born on March 2, 1943. The first draft for service to the Vietnam conflict was limited to men born between 1944 and 1950. Subsequent drafts were for men born in 1951 - 1953. Bubba was born a year too early to have been included in the first draft.
Continuity mistake: During Forrest's first football game, he is standing staring off into space when they receive the kickoff, his teammate runs over to him, hands him the ball, and tells him to run. Forrest says, "Okay". The camera cuts to the coach on the sideline who is yelling for him to "run!, run!", while at the same time his head is turning as if he is watching Forrest run past him. But the next camera shot shows Forrest running, but he has not yet gotten to the point on the sideline where the coach and the team are standing.
Audio problem: During the football match when Forrest runs and bumps into the band players, we hear what sounds like cymbals crashing/dropping to the ground. But if you look at the band players he knocks over, there are no cymbals anywhere near them.
Factual error: In the scene where Forrest's platoon is crouched down along the side of the road, and the narration is introducing some of the soldiers, you can see a pack of Marlboro cigarettes in one of the men's helmets. On the side of the pack is, "Marlboro Miles." These weren't available until the 1990's.
Factual error: When Forrest is talking to Jenny at her grave, he says "You died on a Saturday morning." But 22 March 1982 (the date on the grave) was a Monday.
Continuity mistake: When Bubba and Forrest have just arrived in Vietnam, they are walking along a boardwalk and pass a sign. The shot changes and faces them, but the sign is gone.
Continuity mistake: In the scene where Lt. Dan is waiting on Forrest at the dock, and Forrest jumps overboard off his boat to swim over to meet him, Forrest's hair and face are mysteriously dry for him to have just come out of the water, as if he towelled off his head before climbing the steps up to the platform.
Factual error: In the scene where Forrest Gump is wheeling Lt. Dan across a street between a bunch of taxis, the car they go behind is a 1973 Chevrolet Caprice (see the tail lights). However, several scenes later we know the year is 1971 because it is New Year's Eve 1971 because we see the TV flash 1972 as the year changes.