After attending high school in his native city, he studied at the literature and philosophy department of the University of Bucharest.
After the King Michael Coup of 1944, Theodorescu held important posts at Centrala Cărții publishing overseer, was vice president of the Romanian Writers' Society from 1944 and editor-in-chief of Viața Românească magazine from 1948.
His first book was the 1936 Cleștar, described by Ovid S. Crohmălniceanu as "enclosing the soul's turmoil in glacial, pellucid verses, slowly carved with a jeweler's care".
His later books included Poteca lunii, 1964; Hronic, 1965; Zburătorul din larg, 1965; Țărmul singuratic, 1968; Platoșa duratei, 1973 and Nebunul regelui, 1976.
[1] Theodorescu translated widely, in particular Soviet literature (Vladimir Mayakovsky, Aleksandr Tvardovsky), but also authors who included William Blake, Jérôme Carcopino and Lino Curci.