The Department for Environment, Food and Rural Affairs has given the go-ahead for the trial which would see omega-3 fatty acids usually found in fish added to a crop of camelina plants.
It is reportedly the first ever field trial of nutrient enriched crops in the UK.
Scientists at Rothamsted Research Centre in Hertfordshire who will run the trial hailed the decision as a "significant milestone" for research into genetically-modified plants.
Omega-3 has been proven to be beneficial for human health and contribute to protection against coronary heart diseases.
Researchers spent 10 years designing a sustainable way to produce the oil before successfully growing the engineered plants in lab conditions.
Professor Johnathan Napier, lead scientist of the project at Rothamsted Research, said "We are very pleased to welcome the decision of Defra to grant us permission to carry out our proposed field trial.
"We have made considerable progress over the last 10 years in designing and developing these plants and my colleagues and I am very happy that we can now test the performance of these plants in the field, under real life conditions."
The research is part of a project looking in to how seeds could be enhanced to benefit the population's health.
"Being able to carry out the field trial with our GM plants, means that we have reached a significant milestone in the delivery of our research programme" Professor Napier added.
The controlled experiment will start by mid-May with the plants harvested in August or September this year.
A number of seeds from the plants will be used for analysis, while the rest will be destroyed under the conditions of the consent.
The GM inspectorate of the Food and Environment Research Agency will be carrying out regular inspections.
Professor Martin Parry, acting director of Rothamsted Research, said: "We are delighted to be in position to carry out the field trial and to further assess the potential of these GM plants to contribute, as one of many solutions, to the important environmental sustainability issue of providing omega-3 fish oils"
The trial will be funded by the Biotechnology and Biological Sciences Research Council (BBSRC).
Prof Jackie Hunter, chief executive of the BBSRC, said: "This research is seeking to provide an alternative source of omega-3 oil for the aquaculture industry that is seeking new ways to maintain and increase its sustainability.
"After many years of BBSRC supported laboratory research this project has reached the point where only a field trial will show scientists if this could work in real world conditions. I am pleased that the team are now in a position to proceed and will be interested in hearing their results."