A fuel injection control apparatus for a diesel engine having a plurality of cylinders, wherein each of said cylinders is provided with an injector for injecting a fuel, said fuel injection control apparatus comprising: an ECU including a calculation unit and a storage unit; wherein the calculation unit is starting at a preset crank angle to calculate a fuel injection amount (Q #1) for each cylinder; and wherein the storage unit has a storage area (16a, 16b, 16c, 16d, 16e, 16f, 16g, 16h) corresponding to each cylinder (2,..., 2) and stores by overwriting in the corresponding storage area the calculation result (Q #1) generated by said calculation unit, and an engine rotation sensor; wherein the ECU is calculating the rotation speed of the engine based on the signals detected by the engine rotation sensor; and wherein the ECU is controlling the fuel injector of the first cylinder (#1), which is the cylinder first subjected to fuel injection following the start of the calculation of said fuel injection amount, based at least on the calculated fuel injection amount (Q #1) stored in the corresponding storage area of the said first cylinder (#1); said fuel injection control apparatus being characterized in that the ECU is comparing the rotational speed of the engine with a preset reference rotation speed, when the preset crank angle is reached; and wherein, when the rotation speed of said engine is equal to or lower than the preset reference rotation speed, the calculated fuel injection amount (Q #1) is is stored as well in the corresponding storage area of the first cylinder (#1), as in the corresponding storage area of the following cylinder (#2), which is the cylinder subjected to fuel injection following said first cylinder (#1), and wherein, when said rotation speed of said diesel engine is higher than said reference rotation speed, said calculation result (Q #1) is stored as well in the corresponding storage area of the following cylinder (#2) as in the corresponding storage area of the next following cylinder (#3), which is the cylinder subjected to fuel injection following said following cylinder (#2). an ECU including a calculation unit and a storage unit; wherein the calculation unit is starting at a preset crank angle to calculate a fuel injection amount (Q #1) for each cylinder; and wherein the storage unit has a storage area (16a, 16b, 16c, 16d, 16e, 16f, 16g, 16h) corresponding to each cylinder (2,..., 2) and stores by overwriting in the corresponding storage area the calculation result (Q #1) generated by said calculation unit, and an engine rotation sensor; wherein the ECU is calculating the rotation speed of the engine based on the signals detected by the engine rotation sensor; and wherein the ECU is controlling the fuel injector of the first cylinder (#1), which is the cylinder first subjected to fuel injection following the start of the calculation of said fuel injection amount, based at least on the calculated fuel injection amount (Q #1) stored in the corresponding storage area of the said first cylinder (#1); said fuel injection control apparatus being characterized in that the ECU is comparing the rotational speed of the engine with a preset reference rotation speed, when the preset crank angle is reached; and wherein, when the rotation speed of said engine is equal to or lower than the preset reference rotation speed, the calculated fuel injection amount (Q #1) is is stored as well in the corresponding storage area of the first cylinder (#1), as in the corresponding storage area of the following cylinder (#2), which is the cylinder subjected to fuel injection following said first cylinder (#1), and said fuel injection control apparatus being characterized in that the ECU is comparing the rotational speed of the engine with a preset reference rotation speed, when the preset crank angle is reached; and wherein, when the rotation speed of said engine is equal to or lower than the preset reference rotation speed, the calculated fuel injection amount (Q #1) is is stored as well in the corresponding storage area of the first cylinder (#1), as in the corresponding storage area of the following cylinder (#2), which is the cylinder subjected to fuel injection following said first cylinder (#1), and wherein, when said rotation speed of said diesel engine is higher than said reference rotation speed, said calculation result (Q #1) is stored as well in the corresponding storage area of the following cylinder (#2) as in the corresponding storage area of the next following cylinder (#3), which is the cylinder subjected to fuel injection following said following cylinder (#2).