Injection-enhanced defect transformations in GapLEDs with active layer doped by N (GaP:N), or N, Zn, and 0 (GaP:N Zn-0), as well as AlGaAs:Zn, AlGaAs:Ge, and GaAs:Si LEDs were investigated both theoretically and experimentally. Four principal types of defect transformations were determined to take place in these LEDs. Their nature and parameters were determined from the comparison of theoretical and experimental data.