One of its subsidiaries also made a US$14 million loss, according to the chairman, Dr Tichaendepi Masaya.
Masaya told shareholders that the huge loss was mainly due to loss of business opportunities as well as poor corporate governance issues.
Last week prominent businessman, and Managing Director, Joshua Sachikonye, quit top mining firm which mines among other minerals gold and diamonds.
Sachikonye will leave the struggling but international mining concern at the end of this month.
He stood down at the Extraordinary General Meeting (EGM) held in Harare.
The EGM was held, among other things, to try and thrash out several burning issues including his continued but unpopular tenure in office as Managing Director.
The EGM, however, did not discuss his fate as he had handed his impending resignation to Board Chairman, Dr Tichaendepi Masaya, a former Minister of Economic Planning and Development in Zimbabwe.
Sachikonye has also been Chairman of Trust Financial Holdings Limited (Trust) under top banker William Nyemba.
Trust bounced back onto the Zimbabwe Stock Exchange (ZSE) after having been unceremoniously booted out by the bourse for among other things corporate governance issues.
The Rio Zim EGM was held at its Head Office in Harare and all major shareholders including foreigners were asked to attend the event.
Rio is seriously cash-strapped.
It has a debt of more than US$50 million taken from Barclays Bank of Zimbabwe Limited (Barclays) which is also listed ZSE.
It has now gone cap in hand to shareholders to scrounge around for more funds to recapitalise its operations countrywide.
Rio has been forced to send some of its top heavy Board packing by major shareholders for allegedly abusing funds and running down a once blue chip counter on the ZSE.
Last year shareholders refused the mining giant to beg for more cash from the market shocking the management of the company at its Annual General Meeting (AGM) held in Harare.
Rio mines, among other minerals, diamonds and gold, which ironically is fetching very good prices on the market.
Diamonds from Murowa Mines (Private) Limited, and Chiadzwa in Manicaland are a major source of cash for the cash-strapped nation nowadays.
Murowa Mines (Private) Limited is a major RioZim subsidiary.