The Code of Lekë Dukagjini (Albanian: Kanuni i Lekë Dukagjinit, also known as the Code of the Mountains (Kanuni i Maleve) is one of the variants of the Albanian customary law transmitted orally. Believed to be much older, it was initially codified by the 15th century Albanian Prince of Dukagjini, Lekë. It was only written and published by the Ottoman administration in the first half of the 19th century in Ottoman Turkish in an attempt to stop the blood feuds. It was then compiled by the Catholic clergy at the turn of the 20th century. The collections of the clergy were published in the Albanian language in the periodical magazines as Albania and Hylli i Dritës. The first complete codification of the usual subject saw its first publication in 1933 in Shkodër, a posthumous work of Shtjefën Gjeçovi (killed in 1929) who collected it mainly in the villages of Mirdita and its surroundings.

The Kanun of Lek Dukagjini was named after Lekë Dukagjini (1410–1481), a medieval prince of Dukagjini who ruled in northern Albania and codified the customary laws of the highlands. The code was written down in the 19th century by Shtjefën Gjeçovi and partially published in Hylli i Dritës magazine in 1913. The full version appeared only in 1933 after Gjeçovi's death in 1929.

The text of the Kanun, often contested and with many different interpretations that significantly evolved since the 15th century, was only codified by Dukagjini, not created.

The Kanun is divided into twelve sections, and Gjeçovi's version has 1262 articles regulating all aspects of the mountainous life: economic organisation of the household, hospitality, brotherhood, clan, boundaries, work, marriage, land, and so on. The Besa (personal honor, compare with Latin fides) and nderi (family honor, Latin honor) are of prime importance throughout the code as the cornerstone of personal and social conduct. The Kanun applies to both Christian and Muslim Albanians.

Some of the Kanun's most controversial rules (in particular book 10, section 3) specify how murder is to be handled, which in the past (and sometimes still now) would lead to blood feuds lasting until all men of the two involved families were killed. In situations of murder, tribal law stipulates the principle of koka për kokë (head for a head) where the relatives of the victim are obliged to seek gjakmarrja (blood vengeance). However, this is problematic as although entire families have fallen into blood feuds, the Kanun itself explicitly states that only the initial transgressor is to be targeted in a blood feud, not his family. This is seen in article 898, which states, "Në kanû të veter të Malevet të Shqypnis vetem dorërasi bijte në gjak, ase aj, i cilli tëhiqte, shkrepte e shprazte pushken a çdo armë kundra nierit." Regarded simply as producers of offspring, women are referred to in a discriminatory manner and not considered worthy targets as such. In some parts of the country, the Kanun resembles the Italian vendetta.

These rules resurfaced in the 1990s in Northern Albania, as people had no faith in the powerless local government and police. Some organizations try to mediate between feuding families and get them to "pardon the blood" (Falja e Gjakut), but often the only resort is for adult men to stay in their homes permanently, as they are considered a refuge, or flee the country. Tribal laws also held that thieves would need to pay fines for the relative amount that was stolen.

Albanian tribes from the Dibër valley known as the "Tigers of Dibra" governed themselves according to the Law of Skanderbeg.

The Albanian Bytyqi, Gashi, Gruda, Trieshi, Hoti, Kastrati, Kelmendi, Krasniqi, Shkreli, and Kuçi tribes are known to follow the Kanuni i Malësisë së Madhë, a variant of the Kanun. Its implementation extends from these tribal regions around Shkodër to the Highlands of Gjakova.