The present disclosure relates to a method for controlling regeneration of diesel particulate filter in construction machinery. The regeneration controlling method for the diesel particulate filter of construction machinery according to the present disclosure includes: a first active generation operation of actively regenerating a diesel particulate filter (DPF) according to a predetermined first active regeneration schedule when a quantity of soot inside the DPF within is a predetermined allowance section; and a second active regeneration operation of actively regenerating the diesel particulate filter according to a second active regeneration schedule, which is different from the first active regeneration schedule, according to the quantity of soot when the quantity of soot exceeds the allowance section.