In 1928, he joined the Bulgarian Communist Youth Union (BCYU), an organisation closely linked with the Bulgarian Workers Party (BWP) – later the Bulgarian Communist Party (BCP). The following year he obtained a post at the "Darzhavna pechatnitsa", the official government publisher in Sofia. In 1932, he joined the BWP proper, later serving as secretary of its Second Borough Committee and as a member of its Sofia County Committee. Although the BWP was banned along with all other political parties after the coup of 19 May 1934, it continued fielding a handful of non-party National Assembly Deputies and Zhivkov retained his posts at its Sofia structure.