  This paper is devoted to studying null controllability for a class of
stochastic fourth order semi-discrete parabolic equations, where the spatial
variable is discretized with finite difference scheme and the time is kept as a
continuous variable. For this purpose, we establish a new global Carleman
estimate for a backward stochastic fourth order semi-discrete parabolic
operators, in which the large parameter is connected to the mesh size. A
relaxed observability estimate is established for backward stochastic fourth
order semi-discrete parabolic equations by this new Carleman estimate, with an
explicit observability constant that depends on the discretization parameter
and coefficients of lower order terms. Then, the $\phi$-null controllability of
the stochastic fourth order semi-discrete parabolic equations is proved using
the standard duality technique.
