Nosema, a parasitic disease that affects adult honey bees, has a directly correlation with the losses of bee colonies, until to depopulation. The target of our study was to determine the antinosema action of an apifitoterapeutic formula that was obtained in an earlier phase of our researches. In the present study, we have had two experiences (F and N) formed by clinically healthy bees. The experimental bees have received, in vitro, naturally infested honey (7 spores by Nosema spp / field). The first experience (F, I-IX groups) was treated with apifitoterapeutic formula (10 ml/ honey kg), for 10 days (from T1 to T2 moment), while the second experience (N, with X-XVIII groups) was infested with naturally infested honey, for 20 days (from T1 to T2 moment). The first experience (F) showed 22% positive diagnosed bees, while the second experience (N) showed 89% positive diagnosed bees. In the first experience, the infestation degree was very weak (group I) and weak (group III), while the other groups were negative. The antiparasitic formula has showed, in laboratory conditions, a positive impact on experimental honey bees, with an efficiency over 78%. In the further, testing prophylactically and therapeutically will be conducted on bee families