The present disclosure relates to a hydraulic pressure control device for a swing motor for construction machinery, and more particularly, to a hydraulic pressure control device for a swing motor for construction machinery, which supplements working fluid in the swing motor when a turning operation of an upper body of construction machinery is performed and then stopped. The hydraulic pressure control device for the swing motor for construction machinery according to the present disclosure including the aforementioned configuration may rapidly secure the amount of makeup fluid required by the swing motor when the swing motor is stopped by directly receiving the working fluid discharged from the hydraulic pump P, thereby improving durability of equipment and preventing a cavitation phenomenon.