Abstract: Operation scales are an important aspect of modern livestock and poultry breeding programs in China. However, intensive breeding scales often increase the contradiction between pig breeding scale and eco-environmental factors. Thus, the future development of China's pig breeding industry depends on boosting the scale of operations and curbing the associated environmental pollution. Technological progress, especially green-biased technology, is highly beneficial and optimizes resource allocation, improves pig breeding efficiency, promotes scaled production, and abates pollution. Therefore, it is important to broaden our understanding of the green-biased technological progress in scale of pig breeding operations. This study used data from China's small-, medium-and large-scale pig breeding operations from 2007 to 2017 and systematically calculated the emission of five pollutants generated during the breeding process, which were included as undesirable outputs in the green total factor productivity (GTFP) accounting system. This study also aimed to increase the following marginal contributions to academic discussion. First, the GTFP and the biased technology progress were combined, and not only was the green-biased technological progress in the scale of pig breeding operations in China identified but also the input-oriented green technological progress index was calculated. Second, the input bias of green technology progress was discussed considering the labor force and the concentrated feed input, which affected the long-term survivability and profitability of the pig breeding scale. Third, this study divided the Mainland of China into several meso-geographical units (i.e., key development areas, restricted development areas, potential development areas, and moderate development areas) and discussed whether the green technology progress bias was in harmony with the regional factor endowments. We also presented supporting evidence for the direction of the technological progressions in each area. This paper documented an input-oriented technology progress bias in various scales of pig breeding operations across different areas, and notably, the biases in all areas did not lead to lower GTFP. However, GTFP improvement may stem from a bias for neutral technology progress. The uptrend of technology progress bias in large-scale pig breeding was significant; i.e., the positive effects of technology progress bias on GTFP in pig breeding were increasing. The green technology progress bias for small-, medium-and large-scale pig breeding saved labor by substitutive adoption of concentrated feed. The information presented here indicated that the regional resource endowments determined the biases of technological progress factors in the scale of pig breeding operations in China. Thus, each region should adopt changes in technology based on its resource endowment and environmental regulation objectives.