Beauveria bassiana are usually formulated as conidia infection suspensions CIS for field and laboratory applications as biocontrol agent, but the factors affecting CIS shelf-life and virulence, are unexplored. With the aim of investigating the best storage conditions for extending the CIS shelf-life, the potential effects of storage at room 22 ± 1°C and refrigerated temperatures 4 ± 1°C, with and without light and agitation, on viability and virulence of B. bassiana CISs, was assessed. The viability of conidia was evaluated monthly, over a one year period, and the B. bassiana virulence against D. gallinae, five times in one year. B. bassiana had a significantly higher rate of survival at 4 ± 1°C compared to 22 ± 1°C, regardless of the other conditions of storage. The highest mortality rate of D. gallinae was registered for CIS stored at 4 ± 1°C, in dark and without agitation p<0.05. These results indicate that refrigerating CIS in the dark and without agitation seems to guarantee the best viability and performance of B. bassiana against D. gallinae. Data obtained in this study confirm B. bassiana as potential promising candidate for controlling red mites and provide evidences that appropriate storage condition extend CIS shelf-life for up to one year.