Advances in microbiology demonstrate the need for manipulating individual biological cells, such as for cell injection which includes pronuclei injection and intracytoplasmic injection. Conventionally, cell injection has been conducted manually. In this paper, we present a microrobotic system capable of performing automatic embryo pronuclei DNA injection autonomously and semi-autonomously through a hybrid visual servoing control scheme. After injection, the DNA injected embryos were transferred into a pseudopregnant foster female mouse to reproduce transgenic mice for cancer studies. Experimental results show that the injection success rate was 100%. The system setup, hybrid control scheme and other important issues in this application, such as automatic focusing, are discussed.