During the process of pathogens penetrating the plant cell, pathogens often secret some chemicals into plant cells, at the same time, they also produce mechanical signal by physical pressure on the plant cell. Here the pressure is used as the stress signal, to study its effect on phytoalexin accumulation and the induction of plant resistance in cucumber seedling. It is found that stress can induce the resistance in cucumber seedling significantly. When breaking the plant cell wall and plasma membrane adhesion by RGD peptides, the resistance induction is almost eliminated. Results from TLC and HPLC showed that stress stimulation could increase phytoalexin accumulation in cucumber seedling. This suggests that the accumulation of phytoalexin is one possible reason of the increased resistance after stress stimulation. When the adhesion between plant cell wall and plasma membrane was block by RGD, there is only small amount of phytoalexin accumulation compared with the control, suggesting that the stress induced phytoalexin accumulation and resistance is relying on the adhesion of plant cell wall and plasma membrane.