CityJet is to discontinue its service from Cork to London City Airport from this June.
The scheduled service only commenced last October, and will take off for the last time on June 26th this year.
CityJet's executive chairman, Pat Byrne, said: "In contrast to what we believed to be well-founded optimism when we launched this route last year, we are faced with the reality that demand for this service has simply not taken hold in terms of sustainable commercial viability".
"All the indicators suggested there would be strong support from both business and leisure communities, especially in view of the very significant convenience of City Airport due to its close proximity to the City of London and indeed the West End".
"There is a cost of this convenience as London City is probably one of the more expensive airports in Europe for airlines".
"Unfortunately, with the route now in its eighth month of operation, we have been unable to achieve our passenger load factor and average fare targets," he added.
The airline says the 18 weekly flights failed to gain a market foothold.
But it has thanked Cork Airport and business organisations in the region for "strong and appreciated support".