  By virtue of the well-known theorem, a structure Lie group K of a principal
bundle $P$ is reducible to its closed subgroup H iff there exists a global
section of the quotient bundle P/K. In gauge theory, such sections are treated
as Higgs fields, exemplified by pseudo-Riemannian metrics on a base manifold of
P. Under some conditions, this theorem is extended to principal superbundles in
the category of G-supermanifolds. Given a G-supermanifold M and a graded frame
superbundle over M with a structure general linear supergroup, a reduction of
this structure supergroup to an orthgonal-symplectic supersubgroup is
associated to a supermetric on a G-supermanifold M.
