Under the terms of the deal, PKA and Kirkbi will each own a 25% stake in the project, which is planned to be built 8km off the coast in Liverpool Bay.
Dong Energy CEO Henrik Poulsen said: "Lego Group and PKA are already trusted partners in other Dong Energy offshore wind projects and we are proud to be able to build on these existing, successful partnerships."
The wind farm will feature 32 MHI Vestas wind turbines, each with a capacity of 8MW, to produce clean electricity required to power more than 230,000 households annually.
Lego Group president and CEO Jørgen Vig Knudstorp said: "This investment is another substantial step for the Lego Group towards balancing our global energy consumption with renewable energy capacity."
As part of a long-term deal, Dong Energy will be responsible for operation and maintenance services for the Burbo Bank Extension, which is scheduled to be commissioned in the first half of 2017.
The firm will be responsible for the sale and delivery of the electricity which will be generated by PKA and Kirkbi from the project.
PKA CEO Peter Damgaard Jensen said: "The first investment in a wind farm by PKA was Anholt offshore wind farm in 2011 together with DONG Energy, and today PKA has invested in five offshore wind farms.
"Together they will provide renewable energy to about 2 million households."
