Whey proteins and polysaccharides are two gelling biopolymers widely used in the food industry. Gelation of whey protein isolate (WPI), WPI- κ-carrageenan and WPI-λ-carrageenan mixed systems has been investigated. The apparent viscosity of WPI (3%) solutions significantly increased after polysaccharide addition. The highest apparent viscosity was observed at pH 7 and 0.3% κ-carrageenan. The texture properties of WPI and WPI- polysaccharide systems have been investigated in the pH range 3-10 and κ-carrageenan or λ-carrageenan concentration 0.1-0.5%. In the absence of polysaccharide, very strong and elastic gels were obtained using 10% WPI at pH 7-8. In the presence of κ-carrageenan, the highest shear stress value was observed at pH 7 and 0.3% polysaccharide concentration. Low κ-carrageenan concentrations have been shown to have a major strengthening effect on WPI gels at pH 3 and 6-8. At pH range 3-4, the complexes between biopolymers could be formed, however, at pH range 5-10 the phase separation occurred.