KARI Molo was established as experimental station in 1944 on a farm 5km from Molo town. Research was geared towards the improvement of pyrethrum which was previously introduced Kenya in 1928. The early research work was mainly agronomic and clonal selection. The centre had a mandate on temperate fruits such as apples, pears and plums. During those early days, the centre was known as National Pyrethrum and Horticulture Research station. The centre also run Perkera sub centre which today forms Kari Perkera. With establishment of Kenya Agricultural Research Institute the name of the centre changed to National Pyrethrum Research Centre which in 2002 changed to simply KARI Molo.
KARI Molo (2500m) and has an area of 170 Ha (420 Acres) available for research.  In addition, the Centre has one major sub-Centre in Molo South called Marindas (2800m) with 250 Ha of research land  and four testing sites; Limuru (2300m) , Kari Ol Joro Orok (2200m), Keroka (1700m) and Kari Kisii(1670m).