The Institute had its origins at the University of Oxford, where, in 1924, as the Institute of Agricultural Engineering, it conducted farm machinery trials and undertook research in such topics as subsoiling, haymaking and crop drying.
In 1932 the Institute was renamed the Institute for Research in Agricultural Engineering and in 1934 moved from St Giles in Oxford to larger premises in Parks Road. It become a branch of the Ministry in 1942, and it moved to temporary quarters at Askham Bryan. It was renamed the National Institute of Agricultural Engineering (NIAE).
Priority in the early 1940s was given to testing and educational work although research still continued. Testing was originally done solely for the Ministry, but manufacturers were enthusiastic in having independent testing to assist them in the development of new machines. Training was aimed at those involved as machinery instructors and members of War Agricultural Executive Committees. Correspondence from the war years between the advisory staff and those in involved in food production on the farm throughout the country has been preserved, and gives an insight into the types of problems encountered at this time.
By 1947, the Institute staff numbered 150, and a new home was found at Wrest Park in Bedfordshire.
In 1949 the Institute was transferred to the Agricultural Research Council; this marked a move towards more long term investigation and research and less testing. However, tractor testing always continued in some capacity from the World Agricultural Tractor Trials of 1930, through RASE trials in the 1930s, to later NIAE, BSI, and OECD tests.
In 1986 the Institute became the AFRC (Agriculture and Food Research Council) Institute of Engineering Research (AFRC IER) and in 1991 changed its name to the more manageable Silsoe Research Institute.
In 1994 the Biotechnology and Biological Sciences Research Council (BBSRC) was established and SRI became one of its 8 grant supported institutes. Research during the 1980s and 90s expanded to cover physical, engineering and mathematical applications to agricultural and biological processes and systems.
In 2004, its main sponsoring body, the BBSRC, decided to cease its support due to changes in its own research priorities. Silsoe Research Institute thus ceased operations at the end of March 2006 after 80 years of operation.