This research was conducted to study the microbiological and phytochemical composition of jackfruit and sour-sop smoothies derived from jackfruit and sour-sop. Whole jackfruit and sour-sop with precut jackfruit were purchased from Eke-Awka Market, washed, peeled, cut, and blended with a sterile blender to achieve a jackfruit and sour-sop smoothie. Qualitative phytochemical screening was carried out on the smoothie samples for the detection of saponins, tannins, phenolics, alkaloids, steroids, triterpenes, phlobatannins, glycosides, and flavonoids. A microbiological evaluation of jackfruit and soursop smoothies was also carried out to determine the bacteria and fungi isolates present in the smoothie sample. The total viable bacteria count of 9.1 x 103and the total fungi count of 5.9 x 103 were obtained from the study of the smoothie sample. Escherichia coli, Klebsiella pneumonia, Proteus mirabilis, Enterobacter spp., Shigella spp., and Pseudomonas aeruginosa were the bacteria isolates obtained, while the fungal isolates obtained were Saccharomyces cerevisiae, Penicillium spp., and Aspergillus spp. The bacteria isolated were all gramme-negative, rod-shaped bacteria from the family Enterobacteriaceae. Biochemical characteristics of bacteria isolates, such as gramme staining, catalase tests, coagulase tests, sugar fermentation tests, motility tests, and citrate tests, were carried out. The bacteria isolates were all catalase positive and all coagulase negative, the former indicating the presence of catalase, an enzyme that catalyses the release of oxygen from hydrogen peroxide when broken down, and the latter indicating the absence of Staphylococcus aerus. Phytochemical analyses of jackfruit were carried out, indicating the presence of saponin, tanin, steroids, flavonoids, terpenoids, coumarins, glycosides, triterpenes, phenolics, and alkaloids, and the absence of anthocyanin, amino acids, and phlobatannin. This research helps to exploit the microbiological and phytochemical composition of jackfruit and soursop smoothies. The research is also helpful in determining the microbial contaminants in smoothies purchased to eradicate food poisoning.