The invention discloses a watch large font 24 hour display mechanism. The mechanism mainly comprises a cannon pinion, an idle gear, a time changing component, a command wheel component and a display mechanism. The cannon pinion and the idle gear are engaged. The idle gear transmits energy to the time changing component. The time changing component rotates a circle per hour so that the command wheel component rotates one tooth angle per hour. The command wheel component controls the display mechanism so that each print wheel in the display mechanism rotates regularly according to a set program and time is displayed through figures on the print wheels. The mechanism has the advantages that because single digits and tens digits of 24 hours are independently displayed on different print wheels respectively and the single digits are displayed alternatively by the two print wheels, a typeface is large, display is clear, beautiful and elegant, usage is convenient and an occupation space is small; the structure is simple and reliable; processing difficulty is relatively low and universality is good.