Lavoslav Ružička (13 September 1887 – 26 September 1976) was a Croatian scientist, winner of the 1939 Nobel Prize in Chemistry. He received eight doctorates in science, medicine, and law; seven prizes and medals; and twenty-four honorary memberships in chemical, biochemical, and other scientific societies.
Ružička was born to Stjepan Ružička and Ljubica Severin in Vukovar. He chose to attend the High Technical School in Karlsruhe in Germany. He was a good student in areas he liked and that he thought would be necessary and beneficial in his future, which was organic chemistry.
Later he went to Zurich and was asistent of prof. Hermann Staudinger. He investigated the ingredients of the Dalmatian insect powder, a highly esteemed insecticide. In this way he was interesting to parfume industry and he made a contract with Chuit & Naef Company in Geneva. In one stage of his career he left Zurich and went to the Netherlands. Back to Zurich he became a professor of organic chemistry and started the most brilliant period of his professional career. He widened the area of his research, adding to it the chemistry of higher terpenes and steroids. After the successful synthesis of sex hormones, his laboratory became the world center of organic chemistry.
In 1939, he won the Nobel prize for chemistry with Adolf Butenandt.
Ružička retired in 1957, turning over the running of the laboratory to his assistant and future Nobel laureate Vladimir Prelog. He died in Mammern, Switzerland, a village on Lake Constance.