Background: The literature on theoretically-based programs targeting healthy nutrition and physical activity in preschools is scarce. Purpose: To pilot test CATCH Early Childhood (CEC), a preschool-based nutrition and physical activity program among children ages three to five in Head Start. Methods: The study was conducted in two Head Start centers (N=75 children, their parents; 9 teachers). CEC was implemented by trained teachers over six weeks in fall 2008. Qualitative data on feasibility and acceptability was collected using post-intervention parent and teacher focus groups and lesson plan evaluation forms. Pre-to-post intervention changes in children's fruit and vegetable intake and physical activity at school were evaluated. Results: Results showed good feasibility and acceptability for the classroom curriculum, activity box and parent tip-sheets. There was a trend towards an increase in children's fruit, 100% fruit juice and vegetable intake and mean minutes of physical activity at school pre-to-post intervention. However, this increase was not significant. Discussion: The CEC program showed good feasibility and acceptability in the study population. Further evaluation of behavioral outcomes using a larger sample and a prospective design is needed. Translation to Health Education Practice: These results provide information important for developing and implementing evidence-based programs in preschools.