Based on a curved failure mechanism, an upper bound solution of ultimate pullout capacity of strip plate anchor subjected to pore pressure is derived using the upper bound theorem of limit analysis in conjunction with Hoek-Brown failure criterion. The effect of water pressure which is assumed to be a work rate of external force is included in the upper bound analysis. By employing variational calculation to minimize the objective function, the upper solution of ultimate pullout capacity is obtained. In order to evaluate the validity of the method, the solutions in this paper are compared with the results using linear multiple blocks failure mechanism. The good agreement shows that the curved failure mechanism is an effective method for evaluating the upper solution of ultimate pullout capacity of strip plate anchor.