Recently green house production of cucumber (Cucumis sativa L.) has been increased enormously in I.R.Iran and other parts of the world.This study was conducted to investigate the effects of two exogenous plant growth regulators,IAA and GA3,on production,vegetation,and infrastructure of parthenocarp cucumber (Cucumis sativa),Holland Royal Star cultivar,in greenhouse conditions.Two concentrations of 100 and 500 ppm of IAA and GA3,alone or in combination,was sprayed every week on the plants from when they have 4 leaves and followed for 24 weeks.