Quasiperiodic Ba0.9Sr0.1TiO3 (BST) multilayers have been fabricated on SrTiO3 substrates by using chemical solutions containing polyethylene glycol (PEG), and effect of PEG content on optical properties of the BST multilayers have been investigated. Each multilayer with a single perovskite phase displays a layered structure consisting of dense and porous BST layers. It is found that the central wavelength of the reflection-band for BST multilayers shifts to longer wavelength with increasing the PEG concentration within a given polymer amount range. With the same numbers of period and processing condition, the BST multilayers derived from chemical solutions containing PEG additives with a relative molar amount of 0.5, exhibit the highest optical reflectivities.