Abstract: An open end ratchet wrench includes a socket member rotatably received in an opened head member and having a number of teeth and having an open notch for selectively aligning with an open slot of the head member, a pawl engaged in the head member and having a toothed end for selectively engaging with the teeth of the socket member and for allowing the socket member to be rotated in one direction by the head member, and a retaining ring engaged with the pawl and engaged with the inner peripheral recess of the wrench head member for retaining the pawl to the wrench head member and for allowing the pawl to be engaged with the teeth of the socket member, and a spring biasing member biases the pawl to engage with the teeth of the socket member.