Since Shulman (1986b) argued that pedagogical content knowledge (PCK) should be a significant indicator of teacher knowledge for quality teaching, PCK has received enormous attention from researchers in the teacher education field. Nevertheless, little empirical and theoretical attention has been given to English as a Foreign Language (EFL) teachers’ PCK growth in teachers’ collaborative learning activities (Li et al., 2021). In practice, collaborative learning groups for EFL teachers are often adopted as an effective teacher learning activity as it always integrates observations and discussions of real EFL teaching practices such as English teaching pedagogies and subject matters, for example. However, how EFL teachers’ collaborative learning promotes their PCK growth is less explored by empirical or theoretical studies and some teacher professional growth models. Therefore, this review will mainly discuss via existing literature how EFL teachers could increase their PCK in collaborative learning based on one particular teacher professional growth model, called the Interconnected Model of Professional Growth (IMPG) summarized by Clarke and Hollingsworth (2002). Since IMPG only generally summarizes teachers’ professional growth, this article aims to specifically elaborate the various trajectories of EFL teachers’ PCK growth. The significant role of three essential factors, namely, EFL teachers’ initiatives to learn/share, reciprocal mindset, and reflective dialogues in EFL teachers’ PCK development are stated in the paper. Several recommendations are made to EFL teachers, EFL teacher trainers, and EFL education programs.