Julius Janotha was a Polish pianist, music teacher, and composer of German origin. He lived and worked in Poland from 1850. He was married to Anna Oleszczynska, daughter of Antoni Oleszczynski, and was the father of pianist Natalia Janotha.
In 1859, Janotha accompanied Apollinary Kątski on a tour of Poland to raise funds for the Warsaw Music Institute. He taught piano there from its founding in 1861 until his retirement in 1879, when Paul Schlözer succeeded him. His students included Ignacy Paderewski and Józef Śliwiński.
In the last years of his life, reportedly at his daughter's urging, Janotha turned to composition and published several piano pieces. He died in Warsaw on June 27, 1883, and was buried at Old Powązki Cemetery.