Diro was born in Boku village in the Rigo District of Central Province, the son of a plantation labourer. He was educated at the Boku mission school, Kila Kila High School in Port Moresby and Slade School in Queensland, Australia. He studied at the Officer Cadet School, Portsea, in 1963–1964, becoming a commissioned officer (2nd lieutenant) in the Australian Army. He was promoted to captain in 1967 and to major in 1971, becoming the first Papua New Guinean major in the Royal Pacific Islands Regiment. He was the first Commander of the Papua New Guinea Defence Force from Papua New Guinean independence in 1975, serving until 1981. He was made a Commander of the Order of the British Empire (CBE) in the 1977 Birthday Honours.
Diro was elected to the National Parliament of Papua New Guinea at the 1982 election, winning the Central Provincial seat. He served as Minister for Forests under Paias Wingti from November 1985 to mid-1986, Minister for Foreign Affairs from 1986 to 1987 and Minister Without Portfolio from August to November 1987. He resigned from Cabinet in November 1987 over mounting controversy around alleged corruption while he was Minister for Forests and having received undeclared campaign funds from Leonardus Benjamin Moerdani, the head of the Republic of Indonesia Armed Forces. Despite the ongoing controversy, he returned to Cabinet from April to July 1988 as Minister for State in the last months of the Wingti government, before again returning in that role from May 1989 to April 1990 under Rabbie Namaliu. He was Deputy Prime Minister under Namaliu from April 1990 to October 1991, when he was convicted by a leadership tribunal of 81 counts of official misconduct. The conviction sparked a constitutional crisis when Governor-General Sir Serei Eri, who had been president of Diro's party before assuming the role, purported to reinstate Diro; the resulting controversy saw both Diro and Eri resign.
He returned to parliament at the 1997 election and served a stint as Minister for Agriculture, but was defeated at the 2002 election. In January 2017, he unsuccessfully sought the role of Governor-General of Papua New Guinea, with the term of incumbent Michael Ogio due to expire.
On July 9, 2018, Loop announced that Papua-New Guinea's first Guardian class patrol vessel would be named HMPNGS Ted Diro. Australia had launched the vessel in June, and its sea trials were expected to finish by October. Delivery is scheduled for December, 2018. Diro was present when the vessel was commissioned, on February 1, 2019.
Diro has a primary school named after him.
- Ryan, Peter (ed) (1972). Encyclopedia of Papua and New Guinea. Melbourne University Press. p. 246.CS1 maint: extra text: authors list (link)
- Dorney, Sean (2000). Papua New Guinea: people, politics and history since 1975. ABC Books. pp. 166, 169. ISBN 0733309453.
- "Military-Civil Relations in the Independent State". Government and the Military in Papua New Guinea. Australian National University. Retrieved 9 February 2017.
Jeffrey Wall (2020-03-17). "Protecting democracy in Papua New Guinea". Australian Strategic Policy Institute. Retrieved 2020-03-17.
I had the privilege of mentoring the PNGDF’s first commander, Brigadier General Ted Diro, when he left the defence force and won a seat in parliament at the 1982 national elections.
- "No. 47243". The London Gazette (10th supplement). 10 June 1977. p. 7143.
- "PAPUA NEW GUINEA". Asia Pacific Parliamentary Forum. Retrieved 30 January 2017.
- "A coincidence of G-G election in 1990". PNG Post-Courier. 5 January 2011.
- "Diro: My party will return". PNG Post-Courier. 25 June 2012.
- "Retired Brig Gen Ted Diro vying for GG's post". Loop PNG. 19 January 2017. Retrieved 30 January 2017.
- Cedric Patjole (2018-07-08). "Australian ship named after Ted Diro". Loop.
Miriam Zarriga (2018-10-22). "No talks on new base at Lombrum says Toropo". Post Courier. Retrieved 2018-10-23.
Four Guardian class patrol boats will be gifted to PNG to replace the four with the first boat to be delivered in December and named after the first PNGDF Commander Retired Brigadier General Ted Diro.
Michael Arnold (2019-02-05). "PNCFG vessel named after Diro". Fiji Post Courier. Retrieved 2019-02-05.
Brig-Gen Diro, who was present for the commissioning of the HMPNGS Ted Diro last Friday, along with Major General Gilbert Toropo (current PNGDF commander) saluted the gesture in what both men described as another illustration of the enduring friendship between PNG and Australia.
- Leiao Gerega (2017-05-23). "Ted Diro Primary rewarded by Colgate". Post Courier. Retrieved 2018-10-23.
|New title|| Commander of the Papua New Guinea Defence Force
| Deputy Prime Minister of Papua New Guinea