Inner peace (or peace of mind) refers to a state of being mentally and spiritually at peace, with enough knowledge and understanding to keep oneself strong in the face of discord or stress. Being "at peace" is considered by many to be healthy homeostasis and the opposite of being stressed or anxious. Peace of mind is generally associated with bliss and happiness.

Peace of mind, serenity, and calmness are descriptions of a disposition free from the effects of stress. In some cultures, inner peace is considered a state of consciousness or enlightenment that may be cultivated by various forms of training, such as prayer, meditation, T'ai Chi Ch'uan or yoga, for example. Many spiritual practices refer to this peace as an experience of knowing oneself. Finding inner peace is often associated with traditions such as Buddhism and Hinduism.