Abstract: Disclosed is a system and method for supporting automated self-experimentation based on lifelog data for health behavior change. The system includes a data collection unit configured to collect data related to a user from a plurality of smart terminals and preprocess the data as variables that represent a lifelog of the user; a causal inference unit configured to establish a causal relationship hypothesis between the variables of the user and infer a causal relationship between the variables collected from the user using a statistical analysis method; a variable recommendation unit configured to recommend a variable for verifying the causal relationship through self-experimentation for the user based on an inference result acquired from the causal inference unit and an interaction of the user with the system; and a self-experimentation planning unit configured to plan and conduct an experiment to verify the causal relationship through the self-experimentation for the user.