Microscale cell carriers have recently garnered enormous interest in repairing tissue defects by avoiding substantial open surgeries using implants for tissue regeneration. In this study, the highly open porous microspheres (HOPMs) are fabricated using a microfluidic technique for harboring proliferating skeletal myoblasts and evaluating their feasibility toward cell delivery application in situ. These biocompatible HOPMs with particle sizes of 280–370 µm possess open pores of 10–80 µm and interconnected paths. Such structure of the HOPMs conveniently provide a favorable microenvironment, where the cells are closely arranged in elongated shapes with the deposited extracellular matrix, facilitating cell adhesion and proliferation, as well as augmented myogenic differentiation. Furthermore, in vivo results in mice confirm improved cell retention and vascularization, as well as partial myoblast differentiation. These modular cell‐laden microcarriers potentially allow for in situ tissue construction after minimally invasive delivery providing a convenient means for regeneration medicine. Highly open porous microspheres (HOPMs) are conveniently designed using a microfluidic setup and evaluated for their feasibility toward minimally invasive cell delivery‐based tissue regeneration. These biocompatible HOPMs with interconnected paths facilitate a high cell proliferation rate, and partial differentiation of skeletal myoblasts. These modular cells‐laden microcarriers provide a convenient means for in situ repair of tissue defects and applications in regenerative medicine.