For epoxy microcapsules embedded in concrete as mechanic-triggered self-healing adhesive, globular shape with uniform size is the basic requirement to ensure the solid shell broken and the liquid core released at a designed stress. In this paper, monodispersed melamine–formaldehyde (MF) resin-walled epoxy E-51 microcapsules were successfully fabricated in an in situ polycondensation process, in which a certain amount of polyvinyl alcohol (PVA) solution was added as coemulsifier to control the microcapsules’ shape and size. Detail investigation shows, with the cooperation of PVA, the microcapsule morphologies and size distribution were ease to be adjusted by the parameters such as emulsifying agents, agitation rate, pH value and acidification time.