Work will see construction of a 3,500-capacity digital indoor arena, a coastal park, digital plaza, landmark pedestrian bridge, new car parking and new homes and premises for retail, food and drink.
The PCSA will see Buckingham start a six month period of pre-construction services including detailed design, costings and essential preparatory work on the city centre site.
The early work will prepare the project and site for the main build phase due to start in late summer this year.
The transformation is due to be completed in 2021.
Rob Stewart, leader of Swansea Council, said: “Buckingham Group Contracting has an outstanding record in successfully delivering major high-profile schemes.
“Having a company of this calibre working in collaboration with us is another statement of intent; this will be a world-class transformational scheme that will be a catalyst to making Swansea a great 21st century city.
“We have developed a strategy with Buckingham to offer packages of work to sub contractors and trades, many of whom we hope will be local so the benefits of this significant investment will stay within the local economy’
Kevin Underwood, Managing Director of Buckingham Group Contracting, said: “Our experience of working on major projects means that we’re confident of delivering high-quality work over the next six months.
“We will be committed to delivering the highest standards that this initiative, the people of Swansea and the site’s neighbouring residents and businesses deserve.”