<p>Urban regions in China are presently confronting a significant challenge with the “carbon lock-in” phenomenon, which poses a substantial barrier to achieving the “Dual-Carbon Commitment” and advancing sustainable economic practices. To address this challenge, the strategic application of biased technological progress may offer a viable solution for alleviating the constraints of carbon lock-in. This research utilizes panel data from 282 Chinese cities covering the period from 2006 to 2019, employing an indicator system grounded in the entropy weight approach to evaluate the extent of urban carbon lock-in. It then conducts asymmetric analysis, mechanism validation, and heterogeneity analysis to empirically examine the mechanisms relating to biased technological progress influencing carbon lock-in from various angles. The findings show that biased technological progress significantly alleviates China’s carbon lock-in woes. On average, the carbon lock-in index drops by 0.028% for every 1% rise in biased technological progress. Particularly in cities within the middle and upper quartiles (the latter 50%), with varying degrees of restriction across different city types; pollution control and urban size are the two influencing mechanisms, but the first half of the latter’s propagation path has a “masking effect ”, which is regulated by the regional scientific and educational level. This study innovatively cuts through the biased technology perspective. The findings provide new ideas for solving the carbon lock-in dilemma, and can help policymakers in different regions to tailor their policies to the city, establish a differentiated carbon reduction targets, and strengthen city level governance with a view to achieving sustainable development.</p>