Continuity: When Tiger and Fievel are doing their musical piece, Tiger wipes off the mirror and they appear the same size. When he lays out in front of the mirror, singing the line "We'll be there to pick each other off the floor", he places his head next to the cage bottom, still laying on the floor between them. In the mirror, however, that cage bottom is not reflected at all.

Continuity: Watch the small bed inside the water tower. Soon after the song 'Somewhere Out There', a small piece of cloth appears from nowhere on it.

Factual error: When Fievel arrives on Ellis Island, and the pigeon is telling him that America is bigger than the island they're on, they're standing on the Statue of Liberty's flame. The French gave the arm holding the torch to America in 1876 as a gift to commemorate America's centennial. The arm holding the torch was actually a monument standing in Central Park until the statue was shipped to America and finished.