This paper deals with the stability of multiobjective nonlinear programming problems with fuzzy parameters in the constraint functions. These fuzzy parameters are characterized by fuzzy numbers. Qualitative and quantitative analysis of the basic notions like the set of feasible parameters, the solvability set, the stability sets of the first kind and of the second kind, will be reformulated under the concept of alpha-pareto optimality. An illustrative example is given to clarify the obtained results.