Mutational decreasing of phosphoinositide 3-kinase (PI3K) cascade genes function leads to a life span increase in a lot of model organisms. However the geroprotector effect of pharmacological inhibition of PI3K has not yet been studied. In this connection, we analyzed life span of D. melanogaster wild type laboratory strain Canton-S after treatment by LY-294002 (5 microM), that is a specific inhibitor of PI3K at preimaginal stages of development and imago. It is shown that imago feeding by LY-294002 results in lifespan increase. The median lifespan increases by 14% in males and by 14.3% in females, the maximal--by 22.5% in males, and by 16.3% in females. The obtained results demonstrate that specific inhibition of P13K has a geroprotector effect on D. melanogaster imago.