It comes less than a month after the Post sold its 50 per cent stake in the International Herald Tribune (IHT) to the New York Times.
The Post will continue to provide content to the IHT until the end of March, after which its articles will be published exclusively in the Journal, including in the publication's European edition.
AWSJ editor, Reginald Chua, said that there would not be any material change in the daily as a result of the agreement with the Post.
"There are no plans for branded pages. But the inclusion of Washington Post content will undoubtedly serve to strengthen the overall product.
"We will take articles which our editors feel will be relevant for our readers. These will be run virtually as is and the general feeling is that we will probably take two to four stories per day," Chua said.
He added that the deal with the Post is part of the Journal's ongoing effort worldwide over the past few years to strengthen its content through a variety of means.
This included capitalising on global synergies within the Dow Jones group and introducing new products such as Personal Journal and Technology Journal.