The breeding season for the Gasteracantha cancriformis occurs in the winter, and the female ends up producing between 100 and 260 eggs that develop into offspring. The mating of these spiders is a long process. It begins with the male visiting the female webs and use a rhythmical drumming pattern on the web’s silk. When the male approaches the female, he is strapped down by her silk onto her web, and they copulate. Mating can take at least 35 minutes, and may happen repeatedly.

Once the eggs are fertilized, the female produces an egg sac, containing them all and is deposited under leaves near the nest. Once deposited, the female dies, meaning the eggs have no parental care after this point. But in order to protect the eggs, the female produces an egg case constructed from an ovate egg sheet (made off fine threads firmly attached to the lower leaf surface). The eggs, distributed in an ovate mass, are then covered with a loose, spongy mass of yellow and white threads. Yet another covering is made over the eggs. These are rigid, rough, and dark green. The outer covering of the entire mass is a canopy-like net that she spins over and connects to the leaf. Spiderlings finally disperse when they are mature enough to reproduce (within 2 to 5 weeks).

The life span of this spider is less than a year, starting in winter and ending the following spring.