神义论（英语：theodicy），是一个神学和哲学的分支学科，主要探究上帝内在或基本的至善（或称全善）、全知和全能的性质与罪恶的普遍存在的矛盾关系，这个术语来源于希腊语theos（表示“上帝”）和dike（表示“义”）。由于对其各自对圣典的强调，神义论通常与亚伯拉罕诸教，包括基督教、犹太教和伊斯兰教相关联。神义论的根本论点在于人的罪恶问题：它持续的存在与上帝消灭罪恶的意愿之间的矛盾。最普遍的支持上帝的三全（全爱、全知、全能）的神义论观点认为，罪恶事实上并不像我们定义的那样存在，而且即使是我们所认为“最罪恶”的事情也是上帝能够预见和确保的。一些文献来源使用这一术语来表示对于上帝行为的解释。

Theodicy (/θiːˈɒdɪsi/), in its most common form, attempts to answer the question why a good God permits the manifestation of evil. Theodicy addresses the evidential problem of evil by attempting “to make the existence of an All-knowing, All-powerful and All-good or omnibenevolent God consistent with the existence of evil” or suffering in the world. Unlike a defence, which tries to demonstrate that God's existence is logically possible in the light of evil, a theodicy provides a framework which claims to make God's existence probable. The German mathematician and philosopher Gottfried Leibniz coined the term "theodicy" in 1710 in his work Théodicée, though various responses to the problem of evil had been previously proposed. The British philosopher John Hick traced the history of moral theodicy in his 1966 work, Evil and the God of Love, identifying three major traditions: