In the multimodal (text, audio, and visual) sentiment analysis, the current methods generally consider the bi-modal sentiment interaction, resulting in inadequate mining and fusion of relations between modalities. In this paper, we propose the concept of multimodal 3D (3-Dimensional) stereoscopic attention for the first time, which constructs the tri-modal stereoscopic attention with temporal sequences simultaneously to adequately structure the sentiment interaction. To solve the problems of stereoscopic attention construction such as the increased complexity of algorithms caused by rising dimensions, we propose a progressive construction method with 2D attention as an intermediate process. To implement sentiment relations based on stereoscopic attention to integrating modal information sufficiently, a forward propagation mechanism is proposed, which optimizes the representations of each modality with multimodal modulation. The results on two public datasets confirm the superiority of the proposed method in all metrics to the baselines.