Esther Martinez (1912 – September 16, 2006) was a linguist and storyteller for the Tewa people of New Mexico. Martinez was given the Tewa name P'oe Tsawa (meaning Blue Water) and was also known by various affectionate names, including "Ko'oe Esther" and "Aunt Esther."
Martinez grew up in the southwest. At first, she lived with her parents in Ignacio, Colorado; later, she lived with her grandparents in Ohkay Owingeh. She attended the Santa Fe Indian School and Albuquerque Indian School, graduating in 1930. Over time she developed a great love for the native language of the Tewa; as an adult she would become one of the greatest champions in the fight to preserve this language. That she survived her years in boarding school and went on to help her community by documenting and teaching the Tewa language is a powerful statement, said grandson Matthew J. Martinez.
After graduation, she raised ten children and worked various cooking and cleaning jobs. In the mid-60s, while she was working at John F. Kennedy Middle School in Pueblo, she met a linguist who asked for her help in documenting the Tewa language. From about 1974 to 1989, Martinez taught Tewa at Ohkay Owingeh. She was also the first person to translate the New Testament into Tewa, in association with Wycliffe Bible Translators. She also published a collection of stories My Life In San Juan Pueblo Stories of Esther Martinez University of Illinois Press in 2004. Martinez received an honorary Bachelor of Arts in Early Childhood Education from Northern New Mexico College in 2006.
On September 16, 2006 Martinez was returning home from Washington, D.C. in which she was awarded a National Heritage Fellowship by the National Endowment for the Arts. Near Española, New Mexico the car in which she was riding was hit by another vehicle, whose driver had been drinking. Martinez was killed in this crash.
In December 2006, US H.R.4766, the Esther Martinez Native American Languages Preservation Act, was signed into law; it authorizes funding for new programs that tribes will use to prevent the loss of heritage and culture.
On November 8, 2008, a New Mexico State Historic Maker located on Ohkay Owingeh and dedicated to Esther Martinez, was unveiled and dedicated.