Walter Traupel (23 April 1914 – 18 August 1998) was a Swiss mechanical engineer and professor at the ETH Zurich.
While working at Sulzer, he completed his doctoral thesis at the ETH Zurich and received his PhD degree in 1942.
He was involved in the development of gas turbines and contributed to cycle process designs, flow and heat technical calculations, and stress analysis.
After 16 years of working in the industry, he was appointed as a full professor of Thermal Turbomachinery at ETH Zurich in 1954.
During his time as rector, he emphasized the responsibility of engineers in dealing with the environment and is known for his statement: We are required to have reverence for creation as non-knowers.