Abstract: Structural analysis is an important step during the recognition process of mathematical expressions.And relationships between symbols is a key of structural analysis.However，the indefinition of the relationships often lead to ambiguity.And it has become difficulty to structural analysis of mathematical expression.This paper extracts visible features，and uses multi-features fuzzy pattern recognition to create subjection function in order to judge the relationship by statistic data.The result shows that this method can be applied in wider scope，its correct-rate is higher，and it is more robust.