The Fourth Republic is the current republican government of Nigeria. Since 1999, it has governed the country according to the fourth republican constitution. It was in many ways a revival of the Second Republic, which was in place between 1979 and 1983 and suffers many of the same problems, such as multiple ministries which made policy planning difficult.^{[citation needed]} Nigeria adopted the constitution of the Fourth Republic on 29 May 1999.^[1]

Following the death of military dictator and de facto ruler of Nigeria, General Sani Abacha in 1998, his successor General Abdulsalami Abubakar initiated the transition which heralded Nigeria's return to democratic rule in 1999. The ban on political activities was lifted, and political prisoners were released from detention facilities. The constitution was styled after the ill-fated Second Republic — which saw the Westminster system of government jettisoned for an American presidential system. Political parties were formed (People's Democratic Party (PDP), All Nigeria Peoples Party (ANPP), and Alliance for Democracy (AD)), and elections were set for April 1999. In the widely monitored 1999 election, former military ruler Olusegun Obasanjo was elected on the PDP platform. On 29 May 1999, Obasanjo was sworn in as President and Commander-in-Chief of the Federal Republic of Nigeria.

In the controversial general election on 21 April 2007, Umaru Yar'Adua of the PDP was elected president.

Following the death of Umaru Yar'Adua on 5 May 2010, Goodluck Jonathan became the third president(Interim)^[2] and later won the election the following year which was largely accredited as freer and fairer than all the previous elections of the 4th Republic.^[3] Muhammadu Buhari then won the general elections on 28 March 2015 after the PDP rule of sixteen years (1999–2015).^[4]

On 29 May 2015, Buhari was sworn in as President of Nigeria, becoming the first opposition figure to win a presidential election since independence in 1960.^[5] On 29 May 2019, Muhammadu Buhari was sworn in for a second term as Nigeria's president, after winning the presidential election in February 2019.^[6]

The ruling All Progressives Congress (APC) candidate, Bola Tinubu, won the February 2023 presidential election to succeed Muhammadu Buhari as the next president of Nigeria. However, the opposition had accusations of electoral fraud in polls.^[7] On 29 May 2023, Bola Tinubu was sworn in as Nigeria’s president to succeed Buhari.^[8]

• Third Term Agenda

• Nigerian First Republic (1963–66)
• Nigerian Second Republic (1979–83)
• Nigerian Third Republic (1992–93)

• John A. Ayoade, and Adeoye A. Akinsanya, eds. Nigeria's Critical Election, 2011 (Lexington Books; 2012)