Paddy cultivation is one of the main sources of livelihood, employment and contributors to human nutrition in the rural communities in Sri Lanka. Gender dynamics is an essential element of socio-economic analysis. This research, investigated the gender dynamics in paddy cultivation of three major ethnic communities namely, Sinhala, Tamil and Muslim, in a selected major irrigation scheme in the Vavuniya district. A total number of 156 farm families, including 63 Sinhalese, 63 Tamil and 30 Muslim, were proportionately and randomly selected through stratified sampling technique. A combination of Participatory Rural Appraisal (PRA) tools and a questionnaire survey were used to collect data during Maha season 2010/2011. Among the three communities, household reproductive (non income generating) activities were mostly done by females (93%). Land assets were owned mostly by males (62%), and almost all the machineries were also owned by male family members, thus giving them the access and control over the resources. Both males and females were involved in decision-making related to household activities (81%). However, in all three communities, the major decisions regarding paddy cultivation were either made or influenced by males. The involvement of males in paddy cultivation was higher (71%) than the females in the three communities. In the Sinhala community, involvement of females in paddy cultivation was one-and-a-half and three times higher in comparison to the involvement of females in Tamil and Muslim communities, respectively. Females in the Muslim community got hardly engaged in any field work in paddy cultivation due to their cultural norms. In all three communities, females were placed in an important position in the family to attend to the nutrition, hygiene, childcare, health and education (non-income generating tasks) in comparison to their male counterparts. However, with regard to productive tasks (paddy farming) there were considerable gender differences with regard to ownership and control of resources, decision-making power and involvement in different activities, placing females in a disadvantageous position. Tropical Agricultural Research Vol. 24 (4): 380-390 (2013)