Helen Jernegan (September 8, 1839 – February 26, 1934) was an American woman and wife of a whaler. She began her career as a teacher in 1859 and then married a whaling captain. As he missed his wife, he sent for her to join him and she met him in Honolulu, at that time, within the Sandwich Islands. The two sailed back to New Bedford aboard the Oriole arriving in 1866. Two years later, she went aboard ship with her husband and children, and lived in Honolulu and aboard his ship the Roman until 1871. She sailed twice around Cape Horn and was possibly the first white woman on Tahuata in the Marquesas Islands. After a mutiny on their second voyage, she returned to live on Martha's Vineyard. One of the accounts was written by her young daughter Laura Jernegan Spear.