Prebiotics are water soluble fibers, structurally comprised of unique oligosaccharides. Prominent examples of prebiotic are inulin, FOS (fructooligosaccharides), and GOS (galactooligosaccharides). In this research, four different banana fruits (Musa sp.), tanduk, uli, raja sereh, and cavendish were investigated on their prebiotic activity. Oligosaccharides were first obtained from homogenized fruits (840 gram) which after undergo repeated ethanol extraction and centrifugation, and followed by oligosaccharides detection by thin layer chromatography. Finally, the ethanol extracted purified oligosaccharides (POS) were subjected to freeze dry, and the total yield of each POS from tanduk (TPOS), uli (UPOS), raja sereh (RPOS), and cavendish (CPOS) were 0.2851 gram, 0.6615 gram, 0.9327 gram, and 0.6292 gram, respectively. The prebiotic activity of POS was tested on its growth supporting capacity on probiotic strain L. paracasei, and using E. coli as control. The growth supporting capacity of POS was calculated by using prebiotic activity score (PAS) developed by Huebner et al (2007). Results showed that PAS value ± standard deviation from UPOS, RPOS, CPOS, inulin, and basal are 0.31 ± 0.29, 0.40 ± 0.30, 0.91 ± 1.37, 0.36 ± 0.16, and -0.50 ± 0.85 respectively. PAS from TPOS is inconclusive due to the limited sample testing repetition and fluctuated data. From all results CPOS has higher PAS value than other samples.