As of now, there have been a few women who have successfully completed certain parts of the training pipeline for Navy SEALs, but no woman has yet completed the full SEAL training to become a Navy SEAL. The training for Navy SEALs is extremely rigorous, both physically and mentally, and historically, it has been male-dominated.
However, in 2016, the U.S. military opened all combat roles to women, including the Navy SEALs, so it is possible that in the future, women will successfully complete the training and become Navy SEALs.