PURPOSE: To obtain a gasoline distillate in a high yield by hydrocracking the vacuum distillate oil of a heavy hydrocarbon oil, catalytic cracking the bottom oil obtained by distillation and isolating a light hydrocarbon oil distillate.

CONSTITUTION: This method for producing a light hydrocarbon distillate comprises introducing the vacuum distillate oil of a heavy hydrocarbon oil to a hydrocracker 2 through lines 1a and 1; hydrocracking it with hydrogen introduced through a line 19; distillating in a distillation tower 4; drawing out a gas distillate through a line 12, gasoline distillate through a line 13, kerosine distillate through a line 14 and light oil distillate through a line 15; introducing a bottom oil through a line 5 to a catalytic cracker 6 together with the vacuum distillate oil through a line 11 for catalytic cracking; drawing out coke through a line 16; distillating the product in a distillation tower 8; and drawing out a gasoline distillate through a line 9, intermediate distillate through a line 10, gas distillate through a line 18 and bottom oil through a line 17.