The 165-meter flagpole entered the "Guinness Book of World Records" as the world's tallest in August 2011, in time for the country’s 20th anniversary of independence, which was lavishly celebrated the following month.
It is three meters higher than a giant flagpole in Azerbaijan that previously held the honor as the world's tallest.
The flagpole is located in front of the Kohi Millat, or the president’s exorbitant Palace of Nations complex in downtown Dushanbe.
Several witnesses, including the policeman responsible for guarding the complex, told RFE/RL’s Tajik Service that strong winds brought the flag down during the night of April 23.
Elsewhere in Dushanbe there was damage from the wind, including fallen trees and satellite dishes.
Tajik officials say a new flag will be raised soon.
The flagpole was built by a U.S.-based company, Trident Support, the same company that also built Baku's flagpole.
Azerbaijan had to take down its flag temporarily in February 2011 because the 220-ton pole prompted evacuations of nearby residents when it appeared unstable and slightly bent due to strong winds.
Officially erected in May 2011, the Dushanbe flagpole cost Tajikistan $3.5 million, a fraction of the reported $24-million price tag for Baku's.
In total the impoverished country spent some $210 million on independence-related projects and celebrations.
WATCH: The world's largest flagpole is raised in Tajikistan as part of the country's independence celebrations in 2011.
In this video, soldiers can be seen marching with the flag on September 9, 2011 as part of the country’s Independence Day celebrations.
Tajikistan is the second country to enact a National Flag Day after Turkmenistan. Tajik President Emomali Rahmon signed the law in November 2009. The following week, some 300 Tajik students carried a 90-meter-long flag through the main street in Dushanbe.
Tajikistan remains Central Asia’s poorest country. A total of $3 billion in remittances from Tajik migrant workers in Russia keeps the country’s economy afloat and account for nearly half of the country’s GDP.
-- Deana Kjuka, based on reporting by RFE/RL’s Tajik Service