It said in a statement the money would be used to complete the organic dairy farm being set up by the Lao-Jagro subsidiary in the northern province of Xiangkhouang with 4,000 cows.
It will also invest a high-tech dairy farm with 4,000 cows.
Lao-Jagro was established in 2015 with Vinamilk holding a 51 percent stake and Laotian and Japanese investors the rest to develop dairy farms with Japanese livestock.
Last year it began construction of the first phase of the organic farm on 5,000 hectares at a cost of $120 million, and it will be completed this year.
Vinamilk said the location, Xiangkhouang plateau, has ideal conditions for dairy farming thanks to its similarities to the low hills of New Zealand.