The country's Central Asian neighbours, Turkmenistan, Kazakhstan, Tajikistan and Uzbekistan, have authoritarian presidential systems their leaders say are essential in a region of ethnic and clan rivalries as well as Islamist insurgencies.
"We now embark on a new track, and whatever difficulties we may face, we should learn lessons of true democracy," Kyrgyz interim leader Roza Otunbayeva told deputies after voting.
Alluding to the nomadic roots of the ethnic Kyrgyz, she likened the country's path to that of a "caravan" which becomes more orderly as it travels along.
The new Kyrgyz model of government makes parliament the main decision-making body and gives the prime minister more power than the president.
Candidates for speaker and prime minister, as well as the structure of the government, were proposed to parliament by Ata Zhurt (Motherland), the Social-Democratic Party of Kyrgyzstan and Respublika, which formed a coalition this week.
Ata Zhurt faction leader Akhmatbek Keldibekov was elected speaker by a 101-14 vote in the 120-seat legislature. Deputies later approved Social Democratic Party leader Almazbek Atambayev as prime minister.
Tensions still run high in the impoverished mountainous nation after more than 400 people died in June in ethnic clashes.