Britain could lose its strategic influence over EU science policy if it votes to leave the union, a Lords report has warned.
The science and technology committee of the upper house concluded that UK business lags behind on EU investment, while universities are doing well out of Brussels.
The report also warns that EU membership brings some negative aspects, such as red tape regulations that could prevent innovative research.
The probe heard Britain would still be able to receive EU funds and collaboration after Brexit, but more research was needed on the impact of withdrawal on the UK as "many thought that it would no longer have the same level of high-level strategic influence."
Committee chairman, Lord Selborne, said free movement of scientists and researchers was very beneficial for Britain, but the report had to cut through a lot of "dense Euro-fog" to get to facts.
"The UK science community places a high value on the UK's membership of the EU. Collaboration, funding, facilities and policy make EU membership a key part of the UK's outstanding science base.
"We heard from many witnesses that Brexit would almost certainly result in a loss of strategic scientific influence on the EU stage. As an associated country, or potentially one even further detached, we could no longer have our seat at the decision-making table.
"Many witnesses claimed that the UK is a top performer in the race for R&D (research and development) funding when that is only part of the picture.
"UK universities have outstanding performance in EU funding competitions while UK businesses, in particular large businesses, have low levels of participation and the UK, understandably, does not receive a high level of funding for scientific capacity building," Lord Selborne said.
The committee also found that EU regulation can put British science at a disadvantage with the rest of the world.
The report voices fears British business is losing out on EU money, despite 18.3% of all the UK's incoming Brussels funding going on scientific research and development.
"The Committee is concerned over the poor level of engagement by large businesses in securing EU funding.
"We are below the EU average and lag behind competitor nations such as Germany and France. Given that 64% of research and development in the UK is conducted by businesses, this is a serious failing in the current set-up," Lord Selborne said.