In recent years there has been considerable interest in studying the noise power of the 2D optoelectronic devices under different physical conditions. Besides, the connection of the noise power with the Einstein relation for the diffusivity-mobility ratio of the carriers in optical materials and its influence that further integrate electronic functions with optical devices have extensively been investigated in the literature. Keeping this in view, an attempt is madp fox the first time to study the noise power in 2D optoelectronic devices made of AIB9v type of degenerate opto-electronic materials having non-parabolic and non-dtanaard energy bands. Introduing the anisotropic crystal potential to the Hamiltonian we have first lolerived an E-k dispersion relation of the carriers in the bulk specimens of "B2 v type of opto-electronic materials within the framework of k . p formalism, according to which the conduction band corresponds to a single ellipsoid of revolution at the zone center in k-space by incorporating the anisotropies in the momentum-matrix element and the spin-orbit splitting parameters, respectively, since the anisotropies in the two afore mentioned band parameters are significant physical features of the above class of materials. 'de have then formulated the 2D noise power in the presence of an infinitely deep 1D square potential well leading to the quantization of the wave vectors of the carriers which produces a discrete energy spectrum. It is found, taking n-Cd1P2 as an example which is being currently used as optoelectronic materials and photod6tectors in the near infrared region, that the noise power in 2D optoelectronic devices increases with decreasing film thickness, for a fixed electron concentration, and also increases with increasing surface electron concentration corresponding to a given film thickness. The theoretical formulations are in excellent agreement with the experimental results and the corresponding well-known results for standard devices are also obtained from the expressions derived.