In this paper, we propose visualizing multi-dimensional distribution used in pattern recognition system and construct a visualization system for multi-dimensional space which stimulates intuitive and visual understanding of pattern distribution for the purpose of education. We treat the method of visualizing the multi-dimensional vector data of each character on the handwritten digit recognition system. By applying principal component analysis, the original vectors are converted into principal components and three components. Ellipsoids of equal probability for each category are derived and visualized in the three-dimensional space shown in the visualization system. As a result, the boundary surfaces of each distribution of categories can be seen easily in the reduced three-dimensional space in spite of the fact that visualized vectors distributions do not represent all of vectors data. In conclusion, learners of pattern recognition can be stimulated their interest in and comprehension of multi-dimensional distribution through using this system.