ADELAIDE, AUSTRALIA - OCTOBER 29: Ed Cowan of the Blues bats during day two of the Sheffield Shield match between South Australia and New South Wales at Adelaide Oval on October 29, 2015 in Adelaide, Australia. (Photo by Morne de Klerk/Getty Images)

Former Test opener Ed Cowan has announced his retirement from first-class cricket that included 18 Tests for Australia.

Cowan, who scores 10,097 first-class runs with 25 centuries in 143 matches has announced he is stepping down from cricket.

He will not feature in the NWS Blues final JLT Sheffield Shield match of the season against Queensland in Wollongong next week.

The left-handed opener, who is about to turn 36, will continue to play Premier Cricket with Sydney University, a boost for the club ahead of finals.

"It's been a wonderful journey and I'm grateful for all those who contributed along the way," Cowan said on Wednesday.

"I'll always cherish the great memories and friendships that the game has afforded me. I feel incredibly lucky to have played around the world with so many great people over such a long period of time.

"I'm indebted to NSW Cricket, which invested a lot of time, money and energy in me from a young age. It's equally as important to recognise everyone at Cricket Tasmania, who were hugely formative in my career.

"I have loved the game from my earliest days and feel incredibly lucky to still do so. At this stage I will continue to play Premier Cricket with Sydney University for the remainder of this season and beyond as we aim for successive titles."

The leading run-scorer in the 2016/17 Shield season, Cowan was controversially dumped for the Blues' opening first-class match this summer in favour the younger Daniel Hughes, a decision which national captain Steve Smith took responsibility for.

Once the internationals departed the Blues team Cowan returned and played five of NSW’s nine matches this season, scoring 336 runs at an average of 42.

Cowan scored 68 on Test debut in the 2011 Boxing Day Test against India, before struggling on a three-test tour of the West Indies in early 2012.

He scored his maiden and only Test century at the Gabba against South Africa in 2012, a cool 136 from 257 balls.

He passed fifty once on Australia's ill-fated 2013 tour of India, scoring 86 in Mohali, and his tally of 265 runs for the series was second behind only captain Michael Clarke.

The first Test of the following Ashes tour, also the first of Darren Lehmann's tenure, was Cowan's last as he produced scores of 0 and 14 from number three and was dropped for Usman Khawaja for the following match.