  It is shown that photon--photino inter-conversions (if exist) may result in a
detectable CMBR spectrum distortion which amplitude depends on photino
properties, such as its mass. An upper bound on the distortion parameter
determined from the recent COBE-FIRAS data, hence, sets a lower bound on the
photino mass, $m_{\tilde\gamma} \gtrsim 300 eV$.
