Continuity mistake: At the beginning of the second part Michael returns to his wintry estate. When he enters the house a cigarette appears in his mouth. (00:01:05)
Revealing mistake: In the opening scene you can see Paolo breathing, despite him being dead and all. [If you have trouble seeing it, watch the shadow on his back move up and down as he breathes.] (00:03:05)
Continuity mistake: When Vito's mother asks Don Ciccio to spare her son's life the Don's collar is folded narrow and close to his neck. When the camera cuts to a wide shot before he gets up the collar is wide and flat on his vest. (00:04:20)
Factual error: In the scene of young Vito Corleone coming to America, his ship passes the Statue of Liberty going the wrong way, south, whereas the docks of Manhattan, where immigrants were dropped before being ferried to Ellis Island, are to the north. (00:06:55)
Plot hole: During Godfather I, when Michael was plotting the assassinations of the 5 family heads, he mentions to his father that his son Anthony is thee years old, and 'reading the funny papers.' In Godfather II, we begin at Anthony's first communion, and the date given is 1958. Yet, later at the party, Kay mentions to Michael that 7 years ago he promised the family would be completely legitimate. This was before they married and Anthony was born. (This promise was part of Michael's proposal to Kay.) 7 years ago would be 1951, so how could Anthony be 3 years old then? (00:10:40 - 00:32:20)
Continuity mistake: Al Pacino is accused of killing the 5 family leaders in 1950. In "Godfather part I" the killing of the 5 family leaders took place in 1955. (00:15:20)
Suggested correction: Michael is accused of "devising" the murder of the heads of the five families in 1950. Devising means planning, so while it may have taken about 5 years to successfully carry out, Michael begin planning the murders in 1950.
How is Michael accused of plotting the murder of the heads of the five families, as he himself is head of one of the families, yes five people die but Moe Green is not head of a New York family. It's been a long time since I have seen the film but that always stuck.
For alliteration purposes, five families seems to sound better then four families. Vito also asks for a meeting with the heads of the five families to stop the war, but he is one of the heads so he does not need to say five families, as if Tom would not think to include Vito in the meeting.
This is a common mistake made by viewers. Although there were, in actuality, 5 families in real life, there were 6 families. The script should have said "the other five families..." (or, better yet, just "the other families..." to make it clearer.
Continuity mistake: When Senator Geary talks to Michael in his Lake Tahoe office and the camera is on Michael there's an older couple (the woman is wearing a fur jacket) walking by outside. The camera cuts to Geary for a while, and when it cuts back to Michael the same couple is still walking by. (00:16:15)
Continuity mistake: When the talk between Senator Geary and Michael gets tense the water in Geary's glass doubles. (00:17:15)
Continuity mistake: In the Senate delegtion hearings, Michael made his speech saying he was awarded the Navy Cross. When you see Michael in uniform in Godfather I, he is wearing a Silver Star ribbon. (00:17:25)
Continuity mistake: When Michael tells Fredo that he doesn't want to see him again Fredo is lying shattered in his reclining chair with his arm hanging down. When the camera angle changes Fredo's arm is lying on the armrest. (00:24:45)
Continuity mistake: In the scene where Michael tries to explain to Tom why he has to keep things secret from him, Tom is wearing different pyjamas under his bathrobe in alternating shots. (00:36:50)
Continuity mistake: Shortly after assassins try to kill Michael at his home, he meets privately with Tom Hagen. As Tom enters the room, the table is empty. Then, after they are talking for a few moments, Michael offers Tom a drink from a bottle of courvoisier that has magically appeared. (00:37:20)
Factual error: When Michael arrives at Hyman Roth's house you can see the 1974 State of Florida green inspection sticker on Michael's car. The movie's supposed to be in the late 50's. (00:59:00)
Revealing mistake: In scene at the brothel, with the senator and the dead prostitute, the supposedly dead body is breathing in the last shot of her, just after Tom Hagen says "it'll be as if she never existed". (01:15:30)
Continuity mistake: When Michael and Fredo sit on a restaurant terrace in Havana there's a lady sitting at a table behind Fredo who switches seats back and forth. (01:24:50)
Continuity mistake: When Fredo and Michael are talking at a Café, the red adjuster handle of the parasol is sometimes intact and sometimes it is broken. (01:28:10 - 01:31:10)
Factual error: At the New Year's party, when everybody is running out from the goverment's palace, you see the flags at the entrance are from Cuba, but the coat of arms is from Dominican Republic (the country where this scene was filmed). (01:40:45)
Visible crew/equipment: After the first scene showing the plane starting up its engines and turning around, we are shown another scene of rioters throwing slot machines out of a club. In the bottom centre of the screen you can see a silhouette of what looks to be a part of a jigsaw puzzle piece on the camera. The object must be on the camera because when the camera pans to the right and down, the silhouette stays in the same position in the picture. (01:42:05)
Visible crew/equipment: In one of the flashback scenes Fanucci climbs onto Vito's car. When Fanucci tells him that he and his friends should pay him more respect there's a rather large reflection of the crew in one of the cars driving by. (01:46:50)
Continuity mistake: On the porch in one of the flashback scenes, young Vito is holding baby Michael. Behind them is a guy playing a Gibson-style flat-top guitar that hadn't been invented yet. (02:00:30)