In the digital era, the supply of science workforce determines the growth of an economic system. We compared the impacts of potential factors (gender, socioeconomic status, science achievement, motivations, and epistemic beliefs) on adolescents' science career expectations, and examined whether there were commonalities and differences across academically top-performing economies. Specifically, we contrasted Asian economies [Beijing-Shanghai-Jiangsu-Guangdong (BSJG)—China, Chinese Taipei, Hong Kong, Japan, Korea, Macao, Singapore] against high-achieving or large Western countries with many science-job seekers (Australia, Canada, Estonia, Finland, New Zealand, UK, USA) using the Programme for International Student Assessment (PISA) 2015 data set. Results showed: (a) Although not all Western countries excelled in science achievement in this comparison group, generally they (except Finland and Estonia) had higher instrumental motivation; and attracted more girls, students weak in science, and even low in science enjoyment to join science careers. (b) Singapore was outstanding in having many students attracted to science careers as in the Western economies and had excellent science achievement. (c) Many of the other Asian economies were strong in science, but had relatively low enjoyment, instrumental motivation, and epistemic belief in science; and had fewer adolescents attracted to science careers. Relations between students' characteristics and their career expectations in Science and Engineering, Health Service, and Information and Communications Technology categories were also examined.