The behavior of an excess electron in two-dimensional classical liquid has been studied with the aid of the Chandler, Singh and Richardson (CSR) theory [J. Chem. Phys. 81 (1984) 1975]. The size or dispersion of the wavepacket of a solvated electron is very sensitive to the interaction between the electron and fluid atoms, and exhibits complicated behavior in its density dependence. The behavior is interpreted in terms of an interplay among three causes: the excluded volume effect due to solvent, the pair attractive interaction between the electron and a solvent atom, and a balance of the attractive interactions from different solvent atoms.