There is disclosed a honeycomb structure. A honeycomb structure includes a pillar-shaped honeycomb structure body having partition walls defining a plurality of cells which become through channels for a fluid and extend from a first end face to a second end face, the partition walls are constituted of a porous body having aggregates and a bonding material to bond the aggregates to one another in a state where pores are formed among the aggregates, the aggregates include molten silica particles, the bonding material includes glass, a content ratio of SiO2 in the porous body is 70 mass % or more, and a thermal expansion coefficient of the porous body at 40 to 800° C. is from 1.5 to 6.0×10−6/° C.