International audienceIn relation with the mathematics of financial applications, the present study deals with the solution of the time dependent obstacle problem defined in a three-dimensional domain; this problem arises in the pricing of American options derivatives. In order to solve very quickly large scale algebraic systems derived from the discretization of the obstacle problem, the parallelization of the numerical algorithm is necessary. So, we present parallel synchronous, and more generally asynchronous, iterative algorithms to solve this problem. For the considered problem, arguments implying the convergence of parallel synchronous and asynchronous algorithms are given in a general framework. Finally, computational experiments on ...