A vehicle interior lighting system (1) includes an illuminating unit (50) provided in an interior of a vehicle, an imaging unit (3) that captures a depth image including a distance to an object person in the interior, an estimating unit (83) that estimates a three-dimensional human body model of an object person from a depth image captured by the imaging unit (3), a predicting unit (84) that predicts a movement intention of an object person in an interior based on the human body model estimated by the estimating unit (83), and an operation controller (85) that controls lighting of the illuminating unit (50) according to the movement intention predicted by the predicting unit (84).