Ružička was the recipient of eight honorary doctorates and the 1938 Marcel Benoist Prize. He was listed as author on 583 scientific papers. In 1965, he became an honorary member of the Polish Chemical Society, and he was an honorary member of the American Academy of Arts and Sciences. After the war he acquired a taste for Dutch masterpieces, which he later lodged in the Kunsthaus Zürich as the Ružička collection. He militated against nuclear weapons.
In 1970, Ružička delivered to the Nobel Laureate Conferences in Lindau a lecture entitled "Nobel Prizes and the chemistry of life".
In later years, he served as consultant to Sandoz A. G. of Basel.
Ružička dedicated significant efforts to the problems of education. He insisted on a better organization of academic education and scientific work in the new Yugoslavia, and established the Swiss-Yugoslav Society. Ružička became an honorary academician at the then Yugoslav Academy of Sciences and Arts in Zagreb.
In 1974 he was awarded the Order of the Yugoslav Flag with Golden Wreath.
At ETH Zurich, the Ružička Award was established in 1957 on the occasion of his retirement, for young chemists working in Switzerland.
In his native Vukovar, a museum was opened in his honour in 1977.
Ružička's archives are kept at ETH Zurich.
The Ružička reaction is named after him.