Peter Žiga was born on July 27, 1972 in Košice.
He graduated from the University of Economics in Bratislava in 1995 and the University of Technology in Košice in 2009, specialising in business economy. During his studies he participated in a course for students from eastern Europe, under the auspices of the Union Bank of Switzerland, in St Gallen.
Before starting his political career, Žiga worked as CEO and authorised representative of private companies, but also as the head of the communication department of VÚB bank in Bratislava (1997-1998). Between the years 2003-2004 he served as advisor to the head of the Slovak Investment and Trade Development Agency.
Žiga was first elected to parliament on the slate of Smer party in 2006, but he accepted an executive post instead and was appointed state secretary of the Economy Ministry. He also made it to parliament in 2010 and chaired the committee for controlling military intelligence.
After the 2012 general election, Žiga was appointed minister of the environment.