In the era of knowledge economy, talents concentration plays a key role in the development of a world-class urban agglomeration of Guangdong-Hong Kong-Macao Greater Bay Area (GHM). Based on the population census of Guangdong Province in 2010, the 1% population sampling survey in 2005 and 2015, and employment statistics in Hong Kong and Macao, this study measures the level of talents concentration from two perspectives of educational attainment and occupation on the county scale, and analyzes the evolution pattern and motivations of talents concentration in the GHM. The results show that: (1) GHM is one of the highly developed economic areas in China, and there is the absolute advantage of talents concentration in Hong Kong and Macao, while the level of talents concentration in the Pearl River Delta urban agglomeration is lower than that in the Beijing-Tianjin-Hebei and Yangtze River Delta urban agglomerations. (2) From 2005 to 2015, the spatial distribution of highly-educated talents in the GHM tends to be balanced, and there is also the advantage of the concentration of highly-skilled talents in Hong Kong and Macao. The increasing human capital defined by educational attainment in the mainland, which is caused by the expansion of college enrollment in China, has not been fully and effectively transformed into the advantage of human capital defined by occupation. (3) The level of talents concentration in Hong Kong plays an absolute leading role, followed by Macao, Guangzhou, Zhuhai and Shenzhen, while the counties and cities on the periphery of GHM have a low level of talents concentration. In particular, although Foshan and Dongguan have some developed manufacturing industries, their talents concentration level is relatively low. (4) The panel model shows that the service industry has a greater promoting impact on the concentration of highly-skilled workers than that of highly-educated labors, and manufacturing industry does not influence the talents concentration. Higher education plays a less important role in promoting the agglomeration of highly-skilled workers than that of highly-educated labors. High salary helps promote the concentration of highly-educated workers, while it does not boost the concentration of highly-skilled labors. In the new era, it is urgent to promote the cohesion of management systems in Guangdong, Hong Kong and Macao, the industrial transformation and upgrading, and the establishment of high-quality higher education, ultimately, building GHM into an international innovation center.