史瓦西的研究領域主要是恆星結構和恆星演化。他的研究讓人們更進一步了解脈衝星、太陽的較差自轉、恆星在主序星階段以後在赫羅圖上的演化軌跡（包含恆星如何成為紅巨星）、氫外層來源、氦閃以及星團的年齡等。他大部分的工作是和 Richard Härm 一起進行。而他在1958年出版的書《Structure and Evolution of the Stars》則教一整個世代的天文學家如何應用電腦計算恆星結構與演化模型。
Oral history interview with Martin Schwarzschild. Charles Babbage Institute, University of Minnesota, Minneapolis. Schwarzschild describes his early training in automatic computing when he assumed the position of director of the Watson Scientific Computation Laboratory at Columbia University upon the resignation of Wallace Eckert. Schwarzschild describes the computational research he did there on stellar models, then turns to his experience during World War II at Aberdeen Proving Grounds, mentioning work of John von Neumann and other scientific consultants on the design of new automatic calculating equipment. Schwarzschild answers questions about the relationship between R. H. Kent and von Neumann. His final topic is the work during the 1950s he undertook on stellar interiors using the Institute for Advanced Study computer. He describes his experiences trying to use the computer for large scientific purposes, and recalls the reception of his computational research by the professional astronomy journals.
