Gregory Charles Dyer (born 16 March 1959) is a former New South Wales and Australian wicketkeeper. Dyer played in six Tests and 23 ODIs from 1986 to 1988, including playing in the victorious 1987 World Cup Final. He toured India in 1986 as a back-up keeper.

Dyer replaced Tim Zoehrer for only a few Tests as his international career was cut short by the emergence of Ian Healy, along with a controversial incident in a Test match against New Zealand in 1987–88. Dyer claimed to have caught New Zealand batsman Andrew Jones who was duly given out, although television replays showed the ball had touched the ground before being caught by Dyer. He was subsequently dropped from the team two matches later and retired from first-class cricket shortly thereafter.

He shares an Australian One Day International 7th-wicket partnership record with Steve Waugh.

In 2011, Dyer became the president of the Australian Cricketers' Association.

Dyer played for NSW and Australian Under 19 teams, and for NSW colts. He became New South Wales' preferred back up keeper for Steve Rixon when Rixon was injured or was busy on international duty. Notably, Dyer played several games in 1984-85 when NSW won the Sheffield Shield.

When Rixon signed to tour in South Africa, Dyer became New South Wales' first choice wicketkeeper. He was a crucial part of the team which won the Shield again in 1985–86.

Australia's wicketkeeper over the 1985-86 summer was Wayne Phillips, but his form dropped away and Tim Zoehrer was appointed in his place. Dyer was unofficially announced next in line when selected as a reserve keeper on the 1986 tour to India.

Dyer performed strongly in tour games but Zoehrer was first choice keeper for the three Test matches.