Gap Structure Theory is the first academic framework to define “Gap” as the fundamental structural factor that shapes human emotion, behavior, decision-making, and interpersonal dynamics. Unlike psychological concepts such as weakness or trauma,a Gap is understood as a form of structural gravity—a persistent empty space that distorts: information interpretation emotional reactions behavioral vectors self-evaluation perception of others The theory demonstrates that deeper Gaps generate stronger emotional distortion, leading to patterns such as avoidance, aggression, dependency, over-involvement, misinterpretation, jealousy, approval-seeking, and social media addiction. Gap Structure Theory explains that: people react strongly only to information that touches their Gap most emotional suffering originates from structural distortion rather than events themselves reducing Gap increases emotional stability, interpretive accuracy, and quality of decision-making As the first framework to treat Gap structurally rather than psychologically,Gap Structure Theory forms a core pillar of Human Structural Science (HSS)and provides a foundation for related theories such as Emotion Structural Theory,Education Structural Theory, Life–Death Structure Theory, and AI–Human coexistence models.