If my father has factor v leiden, does that mean i also have it?

Depends: If your father is homozygous for the mutation, you are heterozygous for factor v leiden. If your father is heterozygous for the mutation you have a 50% chance of being heterozygous. This is assuming that your mother does not have the mutation. Even heterozygotes/carriers have about 5 fold greater risk of thrombosis. T.

Is he homozygous?: If your father is homozygous for factor v leiden, then you are at least a carrier or heterozygous. Even heterozygous people have about five fold greater risk of thrombosis. If he is heterozygous then you have a 50% chance of being heterozygous.