Abstract: Biological control is one of the most promising methods, however the success of commercialization of an antagonist depends on its ability to colonize the surface of host plant. The objective of this study was to investigate the survival capability of new antagonists Bacillus subtilis, Pseudomonas vranovensis and Cryptococcus albidus (Yield Plus) under greenhouse conditions. Tomato plants were sprayed with antagonists’ suspension at 1 x10 8 CFU/ml and then inoculation tests were performed. Each of ten days the number of antagonist CFU per 1 cm2 of leaf blade were calculated. It was concluded that: (i) B. subtilis can survive and colonize leaves under greenhouse condition for up to 10 days after the treatment, (ii) B. subtilis survival capability on leaves is comparable to that of C. albidus, (iii) P. vranovensis cannot survive on leaves for a period longer than three days.