In the deepening digital transformation of education, teachers’ digital teaching competencies have become a key indicator influencing their overall capabilities and a core driver for enhancing teaching quality in this educational shift. This paper constructs a framework for cultivating teachers’ blended teaching design capabilities—both online and offline—based on the TPACK framework and considering the context of teachers operating in hybrid learning environments. It summarizes four pathways for improvement. Using random sampling surveys, data related to teachers’ information-based teaching competencies were collected and analyzed with statistical tools. The average score for the seven TPACK components was 3.3065, with a standard deviation of 0.5486. The overall TPACK value exceeded the theoretical median, indicating teachers possess relatively strong capabilities in integrating technological knowledge with subject-specific pedagogical knowledge. Linear regression analysis revealed a regression coefficient of 0.5495 for TPK on TPACK, with a t-value of 7.5486 and P=0.00<0.01. This indicates that TPK exerts a significant positive influence on TPACK, meaning the integration of technological pedagogical content knowledge notably elevates the overall TPACK level. Additionally, teachers with teaching practicum experience had an average TPACK total score of 3.5419, higher than the 3.3214 average of those without such experience. Participating in teaching practicums significantly enhances teachers’ overall TPACK proficiency.