Alginate hydrogels are used in a wide array of applications, such as drug delivery vehicles for chemotherapeutic agents, wound dressing, and tissue engineering, due to their biocompatibility and structural similarity to extracellular matrices in tissues. Here, we present a microfluidic method for synthesizing monodisperse alginate microparticles using flow-focusing emulsification techniques. In this method, two side channels carrying the continuous oil phase intersect with a central channel containing the dispersed aqueous phase, facilitating the formation of uniform droplets where the continuous phase pinches off the dispersed phase into droplets. The microfluidic devices were fabricated using standard soft lithography techniques. A 2% sodium alginate solution, containing sodium EDTA and calcium chloride, was emulsified into ~70 µm droplets. Introducing acetic acid into the oil phase caused a pH reduction within the droplets, disrupting the EDTA–calcium complex and releasing free calcium ions, which induce alginate gelation. After polymerization, a chemical demulsifier was applied to retrieve the aqueous phase containing the hydrogel microparticles, which was subsequently washed and stored in a buffer solution for later use. With modifications to system design and protocol techniques, this method can produce hydrogel microparticles averaging 20-30µm in diameter, while retaining physical characteristics analogous to cellular structures. This approach holds significant potential for biomedical applications, including targeted drug delivery and regenerative medicine.