A rapidly combined chair includes two foot racks, two connecting rods and two plates, the front part and the rear part of every foot rack are respectively provided with straight rod portions, a transverse bar portion is arranged above the front and rear straight rod portions of every foot rack, a back rod portion is arranged at the rear portion of every transverse rod portion, every front straight rod portion is provided with a first bonding portion, every rear straight rod portion is provided with a second bonding portion, every transverse rod portion has an upper surface, a plurality of up-and-down upper straight grooves are downward arranged in the upper surface, the bottom of every upper straight groove is provided with an upper transverse groove, the back rod portion has a front surface, the front surface is backward provided with two fore-and-aft front transverse grooves, and a front straight groove is downward arranged at the rear end of every front transverse groove; the two connecting rods are correspondingly arranged, the center of every connecting rod is provided with a rod portion, and third bonding portions which can be combined with the first and second bonding portions are respectively arranged at two ends of every rod portion; and every plate has a plate portion, nesting grooves for nesting the transverse rod portions and the back rod portions of every foot rack are arranged at two sides of every plate portion, and bonding columns are arranged between two sides of every nesting groove The rapidly combined chair has the advantages of simplicity assembly, easiness in assembling and disassembling, and good combination stability.