Can I still get pregnant doing an IUI with low sperm count of o.5?

Do you mean. 0.5 million? If so the chances with IUI are quite poor I'm sorry to say. That isn't to say impossible, but highly unlikely. Pregnancy rates with IUI are generally no better than 2-3% if sperm are below around 2 million. Talk seriously with your doctor, or A doctor, about ways to be successful. Good luck.