Heinrich Hertz married Elisabeth Doll, the daughter of Max Doll, a professor of geology in Karlsruhe. Elisabeth was a supportive and intelligent partner, providing a stable and loving home environment that allowed Hertz to focus on his research.

Heinrich and Elisabeth Hertz had two daughters, Johanna (born in 1887) and Mathilde (born in 1891). He was a devoted father and took great joy in his family. While his scientific work consumed much of his time, he cherished the moments he spent with his wife and daughters.

Beyond his scientific pursuits, Hertz had a wide range of personal interests. He enjoyed literature, music, and the arts. He was also an avid reader and kept abreast of current events. He had a strong sense of social responsibility and was concerned about the welfare of his community.

In the early 1890s, Hertz began to experience symptoms of what was later diagnosed as granulomatosis with polyangiitis (formerly Wegener's granulomatosis), a rare autoimmune disease. His health gradually deteriorated, affecting his ability to conduct research.

Heinrich Hertz died in Bonn at the age of 36 from blood poisoning caused by granulomatosis with polyangiitis. His untimely death cut short a brilliant scientific career and deprived the world of a remarkable physicist and thinker.