It is shown in this study that photon recycling, i.e., photoluminescence resulting from the self‐absorption of photons generated by prior luminescence processes, affects the steady‐state characteristics of graded‐band‐gap Ga1−xAlxAs : Si LED’s strongly and of constant‐band‐gap GaAs : Si LED’s weakly. In Ga1−x Alx As : Si, where the internal quantum efficiency is near unity, photon recycling can enhance the external quantum efficiency (&eegr;ext) by 25% or more. Moreover, the effective minority‐carrier diffusion length (L) can be augmented by ∼40%. On the other hand, because the internal quantum efficiency in GaAs : Si is considerably less than 100%, the effect of photon recycling on &eegr; andLis less pronounced. A theoretical model of photon recycling in both the graded‐ and constant‐band‐gap material is formulated and its predictions for the effects on the external quantum efficiency, the diffusion length, and the electroluminescent spectrum are in good agreement with the experimental results.