He was one of the most prominent exponents of the Young Slovene political movement. Levstik was the first notable writer of Slovene epic prose. Among his most known works are the short tale Martin Krpan From Vrh (Slovene: Martin Krpan z Vrha), which became a classic work of Slovene literature, and the itinerary A Journey from Litija to Čatež (Popotovanje iz Litije do Čateža), the main objective of which is a literary manifesto.
In the critical essay Napake slovenskega pisanja, he exposed his views on the development of the Slovene literary language.
In his late years, he grew closer to Pan-Slavist ideals. He died in Ljubljana after a period of serious mental illness, which included delusions of a religious nature.
He was buried in the former Saint Christopher"s Cemetery in the Bežigrad district of Ljubljana.
Levstik was one of the main exponents of the Young Slovenes, a progressive and radical political group akin to the Young Czechs in the Czechoslovakian Lands that challenged the then prevailing influence of conservatives, led by Janez Bleiweis, within the Slovenian National Movement. Levstik and his literary program had a great influence on future generations of Slovene authors of national liberal views, especially Josip Jurčič, Josip Stritar, Janko Kersnik, Anton Aškerc, Janez Trdina and Ivan Tavčar.