It is not recommended. You need to find out why you are anemic which is not normal!

It's not recommended to donate blood if you are anemic.

The nice blood bank people will check your blood right then & there. If you are too anemic to donate, call your primary care doctor and get the anemia fixed.

I assume you are referring to donating whole blood. You will not be eligible to donate whole blood if you have anemia. Anemia means a condition in which you have a below normal amount of red blood. Hemoglobin is a measure of the amount of red blood you have. Cut offs for diagnosing anemia are having a hemoglobin less than 12.0 g/dL (for women) or less than 13.0 g/dL (for men). In fact, according to American Red Cross eligibility criteria, you can donate whole blood only if your hemoglobin is at least 12.5 g/dL (for a woman) or at least 13.0 g/dL (for a man).

Anemia, especially moderate to severely low Hgb, is a contraindication for blood donation.