Its revenues remained almost unchanged at $56.7 billion.
Globally, the South Korean giant saw profits surge 122% to $25.3 billion on 16% higher revenues of $220 billion.
The four main factories in Vietnam, Samsung Thai Nguyen, Samsung Electronics Vietnam Bac Ninh and Samsung Display Vietnam Bac Ninh in the north, and Samsung Electronics HCMC CE Complex, contributed 25% to total revenues.
Smartphone manufacturer Samsung Thai Nguyen earned revenues of $22.9 billion, up 7.6% from 2023.
It was the third biggest contributor to sales behind Samsung Electronics America and Samsung Semiconductor, also in the U.S.
But its profits fell by 7.2% to $1.4 billion.
Samsung Electronics Vietnam, another smartphone producer, posted a revenue increase of 5.7% to $14.8 billion.
Its profit jumped 18.9% to $943 million.
The display producer Samsung Display Vietnam saw both revenue and profit declining.
Its revenue fell 15.7% to $14.2 billion while profit dropped by half to $583 million.
The display unit, however, continued to invest substantially in Vietnam last year.
In September it signed a memorandum with Bac Ninh Province for the development of a screen and electronic parts project worth $1.8 billion.
Last month Bac Ninh authorities granted an investment certificate for the subsidiary to pump up its capital by 18% to $7.7 billion.
For the HCMC unit, which makes TVs, profit dropped 5% to $365 million last year, while revenue rose 13.9% to $4.9 billion.
Samsung is the biggest foreign investor in Vietnam with $23.2 billion in registered capital.
Its executives earlier this month have affirmed its commitment to expand its investment in Vietnam, including in new sectors such as semiconductor and AI.