In this paper, a new algorithm called Self-Adaptive Differential Harmony Search (SADHS) algorithm is proposed to solve the dynamic economic and emission dispatch (DEED) problem with security constraints. The searching ability of the proposed algorithm is improved by introducing a self-adaptive method to change the value of mutation constant during run of the algorithm. To show the effectiveness of the proposed algorithm, it is tested on IEEE-30 bus test system with valve point effects, ramp rate limits, prohibited operating zones, and security constraints. The result obtained by the proposed SADHS algorithm is compared with differential harmony search (DHS) algorithm. The result obtained by the proposed algorithm is found to be better than DHS algorithm in terms of solution quality, convergence speed and computational time. © 2014 IEEE.