A one-time programmable (OTP) memory cell, and an OTP memory and a memory system including the same may be provided. The OTP memory cell includes a main OTP cell transistor, a redundant OTP cell transistor, and an access transistor that are connected in series between a first node in a floating state and a second node. The OTP memory cell is configured to apply a program voltage to gates of the main OTP cell transistor and the redundant OTP cell transistor, and a program access voltage lower than the program voltage to a gate of the access transistor, during a program operation.