The poly(acrylic acid)(PAA)-poly(vinylpyrrolidone) (PVP) complexes with different stoichiometric ratio were obtained from aqueous solutions at different concentrations and pH values. The structure of complexes in solutions and in solid state has been studied using mainly FTIR spectroscopy. Least-square curve fitting method has been applied to calculate the contribution of different types of carbonyl groups (free and hydrogen bonded) in the PAA/PVP mixtures. Both polymers and their blends at different compositions were UV-irradiated (lambda = 254 nm) in air. It has been found that PAA/PVP complexes are generally more photostable than pure polymers. This stabilisation effect was explained by the high amount of intermolecular hydrogen bonds reinforcing the polymer structure. Photocrosslinking is an additional factor influencing the stability of PAA/PVP complexes.