More than 40% of Latin Americans in London face "discrimination and work place abuse", a report has claimed.
The study commissioned by the charities Latin American Women's Rights Service and Trust for London found that 85% of the 113,500-strong community had jobs.
But it said half of these workers were stuck in low-skilled jobs and 11% were illegally paid below the minimum wage.
The study by Queen Mary, University of London, said the needs of the community were being "ignored".
The report - No Longer Invisible - said the community was comparable in size to the Polish community in London and had grown four-fold since 2001.
Researchers spoke to focus groups and 1,000 people in the city who have roots in 20 Latin American countries.
The study found that more than half of the population were employed in low-skilled jobs such as cleaning, catering and hospitality, although they had qualifications in teaching, accountancy, engineering and social work.
More than four out of 10 workers said they faced "workplace abuse and exploitation".
Their take-up of public services and state benefits was also low, with one in five saying they had never seen a GP and only 20% saying they had received some form of state welfare benefit.
Almost 70% felt "discrimination to be a major barrier to improving their quality of life".
'Poverty and hardship'
Cindy Sanchez, 22, who came to London from Colombia, said her parents found it hard to integrate. The singer told the study she feels "different" at auditions.
Pedro Quispe who owned a leather business in Bolivia said he found work as a cleaner since coming to London five years ago.
Tania Bronstein, chairwoman of Latin American Women's Rights Service, said: "It is important we are counted, especially by government agencies, so that our contribution and needs are not ignored.
"It is only when we are visible that issues uncovered by this research, such as the low rate of registrations with GPs and dentists by Latin Americans, are identified and can be addressed.
Bharat Mehta, chief executive of Trust for London, said: "Although most of the capital's Latin American community are working hard, many are facing high levels of exploitation and abuse and as a result experiencing significant poverty and hardship.
"We are particularly concerned that such a large number of Latin American workers are being illegally paid below the National Minimum Wage. At 10 times the UK rate there is an urgent need for the government to enforce the law."