张锡纯生活于中西医学初步交汇的年代，主张「衷中参西」——以中医理论为根本，同时吸收借鉴西医的解剖、生理知识及部分诊疗方法，是「中西医汇通学派」的代表人物之一。他所创石膏阿司匹林汤等中西药并用的方剂在当时颇具开创性，晚年在天津创办国医函授学校，将毕生临证经验与学术见解汇编为《医学衷中参西录》，是研究近代中西医汇通思潮的重要文献。

Living through the period when Chinese and Western medicine first began to intersect, Zhang Xichun advocated "rooting in Chinese medicine while drawing on the West" — retaining Chinese medical theory as the foundation while incorporating Western anatomical and physiological knowledge and select treatment methods. He is a leading figure of the "Chinese-Western Medicine Integration" school. His formulas combining gypsum with aspirin, among others, were notably innovative for the time. Late in life he founded a correspondence school for Chinese medicine in Tianjin and compiled his clinical experience and theoretical views into Records of Traditional Chinese Medicine in Harmony with Western Medicine, an important text for studying the early modern integration movement.