Oxalic acid is one of the important acids that is used in many fields. It is of medical, industrial and agricultural importance and is used as an acid in foods, building and construction, pharmacy, and others. This acid is produced in multiple ways, and the biogenic method is the best method because it is safe and cheap. Hence, this study came about, where reliance was placed on wheat bran in preparing nutrient medium to produce oxalic acid from Candida albicans and Aspergillus niger yeast isolated from environmental and pathogenic sources. The study aimed to use wheat bran as an alternative medium for growing fungi and yeasts that produce oxalic acid, and to compare the productivity of this medium with standard media. One hundred fungal isolates were isolated from different environmental and clinical sources, and grown in Sabouraud Dextrose Agar medium (SDA) and Potato dextrose agar to obtain pure isolates of A. niger and C. albicans. Thirty seven isolates of C. albicans and thirty two isolates of A. niger were isolated. Thirty one contaminated samples were discarded. The isolates were grown in standard (SDB, PDB) and alternative (wheat bran WB) media. The amount of acid was estimated by mulching against potassium permanganate The results showed that wheat bran (WB) medium was the most efficient in producing oxalic acid with a rate of 26.2% for A. niger and 25.3% for Candida albicans, compared to standard media. The best temperature for acid production was 32°C with a production rate of 19.1% for A. niger and 22.7% for C. albicans. The best pH was 6.5 for A. niger with a production rate of 20.2% and 5.5 for C. albicans with a production rate of 23.3%. The study conclude from the above that the fungus A. niger is the best compared to C. albicans, as well as the medium of wheat bran is a promising and effective medium in the production of oxalic acid in an environmentally friendly way.