Abstract. HgCdTe photodiodes of relatively large area (Ø = 0.5 mm) for mid-wave infrared region (MWIR) were fabricated on the base of liquid phase epitaxial layers. Characteristics of these photodiodes were estimated to be applicable as those working in background limited performance (BLIP) mode. It was shown that in spectral range of atmospheric transparency λ = 3 to 5 µm obtained dynamical resistance of HgCdTe photodiodes allow to realize their detectivity D* that are restricted by fluctuations of background radiation with specific power of photon fluxes W eff ≈ 3.3·10 -4 -4.4·10 -5 W/cm 2 .