The invention discloses an integrated imaging 3D display device based on a gradual-changing pitch micro lens array. The integrated imaging 3D display device comprises a display screen used for displaying a micro image array and a gradual-changing pitch micro lens array, wherein in the gradual-changing pitch micro lens array, the horizontal pitch of lens units on the same row is the same; the perpendicular pitch of lens units on the same line is the same; the horizontal pitch is gradually increased from the center of the line to the edge of the line; the horizontal pitches and the perpendicular pitches of image units in the micro image array are separately the same as the horizontal pitches and the perpendicular pitches of the lens units corresponding to the image units. When the integrated imaging 3D display device based on the gradual-changing pitch micro lens array is used for imaging, the visual angle seen from a horizontal direction is independent of number of image units in the micro image array, so that the visual angle seen from the horizontal direction of the integrated imaging 3D display device is increased.