Abstract. A three-dimensional H(curl)-elliptic optimal control problem with distributed control and pointwise constraints on the control is considered. We present a residual-type a posteriori error analysis with respect to a curl-conforming edge element approximation of the optimal control problem. Here, the lowest order edge elements of Nédélec's first family are used for the discretization of the state and the control with respect to an adaptively generated family of simplicial triangulations of the computational domain. In particular, the a posteriori error estimator consists of element and face residuals associated with the state equation and the adjoint state equation. The main results are the reliability of the estimator and its efficiency up to oscillations in terms of the data of the problem. In the last part of the paper, numerical results are included which illustrate the performance of the adaptive approach.Key words. Optimal control of PDEs, H(curl)-elliptic problems, curl-conforming edge elements, residual a posteriori error estimator, reliability and efficiency.AMS subject classifications. Primary: 65K10; Secondary: 49M05,65N30,65N50,78M101. Introduction. This paper is devoted to an a posteriori error analysis of adaptive edge element methods for control constrained distributed optimal control of H(curl)-elliptic problems in R 3 . Adaptive edge element methods for H(curl)-elliptic boundary value problems on the basis of residual-type a posteriori error estimators have been initiated in [7,8,31] and later on considered in [11,35]. A convergence analysis has been provided in [24]. For nonstandard discretizations such as Discontinuous Galerkin methods, we refer to [12,25]. In case of the time-harmonic Maxwell equations, convergence and quasi-optimality of adaptive edge element approximations have been established in [42,46] in the spirit of the results obtained in [13] for linear second order elliptic boundary value problems.