It is well known that the laser crystal with mid‐infrared (MIR) broadened and enhanced luminescence is of great significance for various applications, such as atmospheric monitoring, medical surgery and compact and efficient coherent sources. Herein, we exploit the sensitization and deactivation effects of Yb3+/Dy3+ ions to achieve broadening and enhancement ~3 μm emission of Er3+: 4I11/2 → 4I13/2 transition in Yb3+/Er3+/Dy3+: PbF2 crystal. The energy transfer mechanism between Yb3+, Er3+, and Dy3+ was studied. A broadened and enhanced emission with a full width at half maximum (FWHM) of 265 nm was obtained at ~3 μm due to the fact that Er3+ and Dy3+ ions were used as the emission center at the same time. On the one hand, the incorporation of Dy3+ ion can solve the self‐termination bottleneck effect of Er3+ ion, reducing the lifetime of Er3+: 4I13/2 level. On the other hand, Dy3+ ion can …