After his father's assassination, Kadyrov became deputy prime minister and in March 2006 he replaced Sergey Abramov, the then prime minister.
In the course of his political career, Kadyrov has implemented a number of Islamic reforms in Chechnya and is an advocate of polygamy.
In 2006, Human Rights Watch, a New York-based rights group, released a report saying security forces under the control of Kadyrov "hold and torture detainees in premises that are not lawful places of detention".
The report said: "Victims, interviewed separately, consistently described the administration of electric shocks through a portable device ... [with wires] that the torturers attached to the victims' fingers, toes, ears, or other body parts."
Kadyrov has always denied allegations of human rights abuses.
With help from Kadyrov's security forces, the Russian military has killed most of the Chechen rebel leaders and driven their fighters into mountain hideouts from where they launch occasional guerrilla-style attacks.
Moscow has financed much of the rebuilding in Grozny and Chechnya, for which Kadyrov has taken credit.
But some analysts say the relationship between Kadyrov and the Kremlin could fall apart after Putin steps down in 2008.
"Putin has given Kadyrov the presidency himself and it will be okay until the next presidential election," Alexei Malashenko, a Caucasus expert at the Carnegie Moscow Center, said. "But when the next president comes to power Kadyrov could be in trouble."
Officials in the Russian security services are wary of the power and influence Kadyrov has accumulated.
Grigory Shvedov, chief editor of the online newspaper Kavkazsky Uzel, said Kadyrov might become an "uncontrollable leader" for Moscow.
"He feels he is a tribal leader ready to defend Chechens all over Russia," Shvedov said.
"He is loyal to Putin, but it is a medieval loyalty to a man, not to a territory."
Located between the Caspian and Black Seas in the Caucasus mountains, Chechnya has fought several wars, from 1994-1996 and again from 1999, for independence from Russia.
"Chechen society is profoundly split. Those who were loyal to Moscow are now outraged that former rebels are in power," said Malashenko.