Q3 2015 Operational Update - 13,760 oz Gold Produced at US$876/oz Cash Costs

Orosur Mining Inc. (the "Company" or “Orosur”) (TSX:OMI) (LSE: OMI), a South American focused gold producer, developer and explorer is pleased to announce its operating results for the third quarter of its fiscal 2015 ended 28 February 2015 (“Q3 2015” or the “Quarter”).

HIGHLIGHTS:

During the Quarter gold production from Arenal Deeps accounted for approximately 65% of total production, representing a 20% increase from the previous quarter. The Company expects this figure to increase above 70% during Q4 2015. As per the mine plan, the Company returned to mining higher grade, larger transverse stopes in Q3 2015 and as such expects further reductions in operating cash costs in Q4 2015.

Orosur continues to focus on cost reduction initiatives, including optimizing corporate and operational teams, geological modelling, mine planning, and fleet use.

Q4 2015 production is expected to be mined primarily from Arenal underground and the new Laureles open pit mine. The Company maintains its production forecast for FY2015 of 50,000 to 55,000 oz of gold at operating cash costs of approximately US$850 -$950/oz of gold. Orosur expects its Q4 2015 results to exceed those in the previous quarters of 2015 due to an increase in ore mined and higher grade from Arenal both driving up production and reducing costs, the commissioning of the Laureles open pit mine and the ceasing of expenditures related to commissioning the new tailings dam.

Laureles Open Pit Mine

During the Quarter, the Minister of Mines signed the Concession and Easement required for Orosur to commence construction and mining at its Laureles open pit mine. Preparatory work at Laureles has since commenced and the Company expects this to be the primary source of open pit ore for the next six months and provide a steady complement to ore from Arenal. Further exploration work is underway at Laureles, as the mineralization is open on strike and down dip.

New Tailings Dam

During the Quarter, closure of the existing tailings dam and construction of phase 2B of the second tailings damn was finalized. This work was completed on time and within the initial budget of approximately US$3 million. The new phase of the tailings dam is designed to provide tailings capacity for at least 18 months.

Ignacio Salazar, CEO of the Orosur commented:

“Orosur has achieved quarterly operating results slightly ahead of our stated guidance and has reduced cash costs by 9% over the first half of our fiscal year, as planned. We continue to demonstrate solid operational performance, and are implementing initiatives to further optimize operations. Operational achievements in this quarter include the successful permitting of the new Laureles open pit mine, closure of the old tailings dam and completion of a new phase in our second tailings dam. In a challenging gold price environment, we are pleased to continue making progress at our operations and anticipate a solid fourth quarter to come. Our intention remains to continue delivering operational improvements both in the short and long term to generate further value for our shareholders.”

Qualified Person's Statement

The scientific and technical information related to the current assets of Orosur Mining in this press release has been reviewed and approved by Michael Schwabe, an Exploration Consultant who is a Qualified Person under NI 43-101 reporting guidelines. Mr. Schwabe is a graduate in Science, majoring in Geology from the University of Tasmania and is Fellow of the Australian Institute of Mining and Metallurgy, a Senior Fellow of the Society of Economic Geologists and a Professional Member of the Society for Mining, Metallurgy and Exploration. Mr. Schwabe has 47 years of professional experience in the field of mineral exploration, mine development and management.

About Orosur Mining Inc.

Orosur Mining Inc. is a fully integrated gold producer, developer and exploration company focused on identifying and advancing gold projects in South America. The Company operates the only producing gold mine in Uruguay (San Gregorio), and has assembled an exploration portfolio of high quality assets in Uruguay, Chile and Colombia. The Company is quoted in Canada (TSX:OMI) and London (AIM:OMI).

For more information please visit www.orosur.ca

Orosur Mining IncIgnacio Salazar, + 562 2924 6800Chief Executive Officerinfo@orosur.caorCantor Fitzgerald EuropeStewart Dickson / Jeremy Stephenson+44 (0) 20 7894 7000orFTI ConsultingBen Brewerton / Oliver Winters / Sara Powell+44 (0) 20 3727 1000