The blood colour in cockroach is:

The cockroach blood colour is pale white or colorless. This is because cockroach blood does not contain hemoglobin, the pigment that gives human blood its red colour.

In cockroaches, the circulatory system is of the "open type," meaning that the blood, also called hemolymph, flows freely in the body cavity and directly touches all the internal organs. Since hemoglobin is absent in their hemolymph, it does not carry oxygen like in humans. Instead, cockroaches use a system of tubes called tracheae for breathing, so oxygen transport doesn’t rely on their blood.

The cockroach blood colour remains pale because its main role is to transport nutrients and waste, not oxygen.