Porous alumina (Al2O3) beads were prepared via gel-dripping and pressureless sintering with α-Al2O3 as a raw material, nontoxic sodium alginate as a gelation reagent, and the calcium ions were introduced in the preparation using a calcium chloride solution. The effects of coagulation time and sintering temperature on the porosity, compressive strength and microstructure of porous Al2O3 beads were investigated. The results show that calcium ions can transfer and react readily with sodium alginate as the coagulation time increases. Alumina particles are solidified to form a bead green body by a three-dimensional network. The number of meso-pores decreases and the microstructure becomes well-distributed with increasing the sintering temperature. The porosity and compressive strength are 47.7%-78.1% and 1.2-36.0 MPa, respectively. The porosity, pore structure and compressive strength can be tailored by optimizing the coagulation time, sintering temperature and calcium ion concentration. The diameter, sphericity and property of porous alumina beads can be controlled through the simple gel-dripping method. The porous alumina beads can be used in many fields, such as catalyst support, adsorption, separation, purification, etc..