The effect of type and level of two prebiotics (as fat replacers) on the quality attributes of low-fat set yoghurt was firstly studied. Inulin or polydextrose, each at 1, 2 or 3 g/100 mL of reconstituted milk, were used for evaluation of the product's properties. The addition of each prebiotic could improve physical and sensory properties of the yoghurt and 2 g of polydextrose/100 mL was the most suitable level. Secondly, the probiotic-cultured (with Lactobacillus paracasei Lpc-37) banana purée was prepared and used as fruit base of the product (with the set-yoghurt on top) and some physicochemical and microbiological characteristics were monitored during 21 days of storage. The number of the probiotics was still highly acceptable at 8.86 log CFU/g during the entire storage period; however, its physical properties gradually deteriorated after 14 days.