Do individuals use video sharing sites in their free time to learn about science, and if so, why? This study takes a preliminary look at individual differences that motivate online science video seeking. Among 273 Singapore Internet users who participated in an online survey, most reported using YouTube during the previous week, and one-third reported using it to watch science videos. Hierarchical regression analysis explained 55% of the variance in their intention to seek science videos during the subsequent week. Significant predictors of interest were seeking-related subjective norm, enjoyment of science, and informational use of YouTube. Although these results do not distinguish YouTube from other venues of informal science learning, they help characterize YouTube as such a venue and have implications for developing online video content to promote science learning in everyday life.