Studies on proximate analysis and lower fungi interaction with post-harvest storage of Phallus indusiatus were carried out in the laboratory of Department of Microbiology and Botany, University of Ibadan, Nigeria, and laboratory of International Institute of Tropical Agriculture (IITA) Ibadan, Nigeria. The objectives of the studies were to collect and identify Phallus indusiatus; determine the proximate composition in different parts of the mushroom; determine the mineral composition of the soil where P. industiatus was harvested; isolate and identify fungi that caused bio-deterioration of stored Phallus indusiatus and to isolate and identify soil inhabiting fungi from the soil where Phallus indusiatus was harvested. Harvested fruits bodies of Phallus industiatus were divided and samples oven-dried at 80% for 48 hours and powdered in electric blender, the powdered samples were stored in the desiccators for further use, the mineral elements were analyzed in the laboratory of (IITA) using atomic absorption spectrophotometer, flame photometer and phophoranado-molybdate reaction, the crude fibre and ash were analyzed by (AOAC) method, the sugar and lipid were analyzed by Soxhlet extraction method and determined, dry matter and protein content were analyzed by taking weight difference after drying and centrifugation method respectively. The associated fungi were isolated, characterized and identified in reference to Microbiology Manual, morphological and physiological observations. The results showed that stipe had the highest amount of sugar (6.50%), protein was highest in the veil (42.63%), egg stage had the highest amount of fibre (20.90%), lipid (1.60%) and moisture content (88.76%), the highest amount of ash was found in the volva while the highest dry matter was found in pileus (1.57%), Mg was the highest in volva, veil had the highest amount of Fe though it was small in all the parts, it was mostly found in the stipe. Na, Mn, Zn, and Cu were very low in all the parts, the highest amount of Zn was found in the egg stage. Elements obtained from the soil where Phallus indusiatus was harvested were generally low, Ca was most abundant (0.39%) while the least was Cu (0.03%), among the identified fungi associated with post harvest Phallus indusiatus were: Rhizopus stolonifer, Mucor racemous, Aspergillus niger, Aspergillus flavus, Aspergillus nidulans while the fungal isolates from the soil where Phallus indusiatus was harvested were: Aspergillus niger, Aspergillus flavus, Aspergillus vessicolor, Fusarium oxysporum, Penicillum notatum, Verticillum arbo-atrum, Rhizopus stolonifer, Botytis cinera, Aspergillus amstelodami, Aspergillus terrens and Aspergillus japonicum. The most abundant elements found in the Phallus indusiatus are: Mg and K in the volva and stipe respectively. Mg and Na are vital minerals in many cellular activities such as acid base balance (buffer), water and salt balance (osmo-regulation) in the body, nerve functions, enzymatic activities and body building; Ca is needed for strong bones and teeth formation. Phallus indusiatus is a good source of food and some associated fungi are found to be responsible for its bio-deterioration.