The invention discloses a multifunctional children shoe with the space in the shoe adjustable. The multifunctional children shoe comprises a shoe sole and a shoe upper, and the shoe upper is arranged on the upper portion of the shoe sole; the shoe upper comprises a shoe head part arranged in the front, shoe side parts arranged on both sides of the shoe and a shoe rear part arranged in the rear of the shoe, the shoe upper is provided with a shoe outer layer, a cushion layer, a wear-resistant layer and a lining layer from outside to inside in sequence, and multiple air bags distributed from top to bottom are arranged between the cushion layer and the wear-resistant layer of the shoe rear part. According to the multifunctional children shoe with the space in the shoe adjustable, real-time adjustment can be conducted based on the size of a child foot, the comfort of the child foot is satisfied, meanwhile the service life of the shoe can be prolonged, and the economic pressure of family life is relieved; besides, heating can be conducted through a heating piece arranged in the shoe in chilly winter, the temperature in the shoe is improved, the situation that the child foot gets frozen is avoided, improvement of the study efficiency in class is promoted, and an adverse influence on child health is prevented.