The work took a month longer than usual because several urgent tasks needed to be addressed.
The Ho Chi Minh Mausoleum will reopen to visitors on Tuesday after three months of annual maintenance work.
The public reopening follows an inspection conducted by Prime Minister Nguyen Xuan Phuc to appraise the work.
Officials said the work took a month longer than in previous years because several important issues needed to be addressed, Giao Thong Newspaper reported.
The granite memorial sits in the center of Ba Dinh Square and was built on the spot where Ho Chi Minh read the Declaration of Independence on September 2, 1945, establishing the Democratic Republic of Vietnam. It opened in 1973, inspired by Lenin’s mausoleum in Moscow.
Thousands of people visit the memorial every year, making it one Hanoi’s most popular attractions. Managers of the mausoleum said visitor numbers in 2017 had increased nearly 12 percent from a year ago.
There is a strict dress code for visitors that requires them to have their legs covered.
It is normally open to the public from 7.30 a.m. to 10.30 a.m., except on Mondays and Fridays.
At night, visitors can also view the mausoleum lit up and an impressive flag ceremony.
The nearby Ho Chi Minh Museum and Presidential Palace have remained opened during the maintenance work.