Penicillium oxalicum Curie et Thom isolated from blossom of mango (var. Saddekia) was evaluated against mango malformation incited by Fu- sarium subglutinis. Both in vitro and in vivo conditions. The mechanism of this isolate for controlling Fusarium was the reduction of growth development. The Penicillium oxalicum isolate produced extracellular cellulolytic enzymes (exo-glucanase or cellobiohydrolases and endo-glucanase, that possibly related to the biocontrol process. Optimize and fermentation conditions (growth period, carbon and nitrogen sources) for spores and cellulolytic enzymes production were determined. Liquid formulation containing (6 × 10⁶) with sodium alginate (0.5%) and Tween 80 (0.01%) was used. For field evaluation, susceptible cultivars as Ewais, Saddika, Alphonso, Taimour and Zebda were selected. Liquid bioformulations were sprayed twice and 30 days intervals. The spray was initiated from pre-flowering stage. Bioformulation was found to be significant in reducing the malformation incidence. Results cleared that spraying of liquid bioformulations, substantially improved the fruit numbers and yield for the five mango cultivars and suggested to be most promotive for fairly quality in tested cultivars.