In this talk, a pointwise weighted identity for a class of stochastic partial differential operators  is established. This identity presents a unified approach of studying the controllability, observability and inverse problems for deterministic/stochastic PDEs. Based on this identity, one can deduce all known Carleman estimates and observability results, for some deterministic PDEs, stochastic heat equations, stochastic Schrodinger equations and stochastic transport equations. As its applications, one can establish a global Carleman estimate for the linearized stochastic complex Ginzburg-Landau equations and study the inverse problems for them.