Pre-sterilization cleaning of fruit by the removal of calyx is a common practice by Nigeria Small Scale Palm Oil producers. They manually pick palm fruits or repose fruits along inclined wire gauze to achieve the separation of calyx from fruits. These manual methods are slow, labour demanding and arduous. An Oil Palm Fruit Screen was designed (in the Research Engineering Division of NIFOR) to separate calyx from oil palm fruits (prior to fruit sterilization) and to clean fruits thereby improving oil palm fruit quality in the Small Scale Processing Engineering (SSPE) outfit used at NIFOR. In the evaluation of the machine, harvested oil palm fruit naturally containing calyx was screened. Known weights of palm fruit and calyx mixed in various proportions were also screened in the machine. Consistently, over 80% separation was obtained whenever a mixture of fruit and calyx is subjected to the machine. This result shows that the incorporation of this screen in the SSPE enhances pre-sterilization cleaning of palm fruits thereby improving the overall efficiency of the Small Scale Processing Equipment in terms of oil yield and quality. (c) 2004 Published by Elsevier Ltd.