Information and Communication Technologies (ICT) have a remarkable potential to improve the agricultural practices and innovation systems and to achieve significant benefits. To achieve the complete benefits of ICT, it is better to understand the constraints in ICT adoption for agricultural development, identify feasible options for reducing the constraints and contribute to develop effective policies at increasing the use of ICT. This study investigated the adoption of Information Communication Technology (ICT) in cashew sector which represents estates owned and managed both by small holders and plantation companies. A questionnaire based survey was conducted to collect data from 50 Small Holder cashew estates and 26 Plantation Company owned cashew estates in Puttalam District of Sri Lanka. To quantify the adoption of ICT, three indices were developed viz., Primary ICT Adoption Index.,, Secondary ICT Adoption Index. and, Tertiary ICT Adoption Index.. Further, t test was carried out to find out the relationship between the ICT adoption index of Small Holder cashew estates and Plantation Company owned cashew estates. Eight statements were used to calculate the attitudinal percentage of ICT of managers and owners. The results show that these estates were not innovative ICT by adopting Tertiary or Secondary type of technologies; however they were mostly confined to the basic facilities. The results from the three indices highlighted that the plantation company owned estates have higher ICT adoption than small holders. According to the analysis, no significant relationship was observed between ICT adoption and working experience and age of the managers, number of employees in the estate and cashew production. However, a positive relationship was observed between education level and the ICT adoption in the cashew sector in Puttalam district.