Paku, 42, is a product of Hato Paora and St Stephens' Colleges and a former New Zealand Secondary Schoolboys representative. He then played for Wellington, Auckland, Manawatū, and the Hurricanes and shared a Super Rugby title with the Blues. He had a stint with Montauban in France and was also a Maori All Black and a New Zealand Under-21 representative.
Once retiring, Paku ran his logistics company in Wellington in 2010 and became one of Wellington's board of directors in 2015.
Paku also had three years as chief executive of the Manawatū Rugby Union.
He said he was excited to take the Wellington role.
"I became a professional rugby player here, proudly donning Wellington's black and yellow jersey over seven seasons, so it's quite a special place for me.
"I have good relationships with many of Wellington's past chief executives and many former players who have now come in as coaches and administrators.
"I know there are some challenges, but there are also a lot of amazing things happening in this Union and a lot of dedicated people.
"The landscape of provincial rugby, and the various challenges we face in today's climate, are very familiar to me, and I am looking forward to bringing this experience into the role," he said.
WRFU chairman Russell Poole the Union welcomed Paku's business acumen, and he brought a wealth of experience from both on and off the field.
"We're excited and pleased to have secured Shannon's services as our chief executive. First and foremost, Shannon is a great person aligned with the WRFU.
"From a functional perspective, he previously served one year on our board and filled the Manawatū chief executive's role for three years, so is fully conversant with the rugby environment from community participation through to our high-performance environment such as the Pride, Lions, Centurions development and Under-19 teams."