Abstract: By feat of category theory, the impact mechanism of actualization consequences of decision alternatives shared among decision units on improving organizational decision-making was explored. The concept of information-sharing was presented. Then, organizational decision-making was formulated as a category comprised of organizational decision situations, and morphism between decision situations was defined to reflect the information-sharing conjunction. The relationship between decision situation and organizational decision solution set was established through functors. The study argues that information-sharing cause expansion of organizational decision solution set and enable organization to optimize its decision on an expanded solution set, thereby avoid or reduce the possibility of leaving out the better solution due to information imperfection.