Paula Kane Robinson Arai is an American professor and Buddhist studies scholar, specializing in the academic study of women and Buddhism, specifically Jōdo Shinshū Buddhism and Japanese Sōtō Zen women. She has also been an active public speaker and led workshops on healing rituals.

Arai, who grew up in Detroit, Michigan, earned her Ph.D. in comparative religion and Japanese Buddhism from Harvard University. While still a student, she began conducting ethnographic and historical research about Japanese Zen nuns, which eventually became her first book, Women Living Zen: Japanese Soto Buddhist Nuns (1999). She taught courses in Buddhism, Asian religions, and theories of religion at Louisiana State University and is currently a member of the faculty at the Institute of Buddhist Studies in Berkeley, California. She is a practitioner of the religious traditions she studies; her work is grounded in ethnographic research and her pedagogical approach "blends a rigorous academic background with a compassionate, embodied, and person-centered approach to teaching". She has been awarded several research grants and teaching honors.

Arai has written four additional books, as well as a long list of journal articles. She published Bringing Zen Home: The Healing Heart of Japanese Women's Rituals in 2011, in which she studied, the religious and spiritual practices of 12 lay women, whom she called her "consociates", ranging from their 40s to their 70s. in 2019, Arai published Painting Enlightenment: Healing Visions of the Heart Sutra—The Buddhist Art of Iwasaki Tsuneo, which studies and analyzes the work of Iwasaki Tsuneo (1917-2002), a Japanese biologist and Buddhist artist. in 2022, she co-edited the Oxford Handbook of Buddhist Practice, and in 2023, she published The Little Book of Zen Healing.

Paula Arai grew up in Detroit, Michigan, the daughter of Lucian Ford Robinson, who was Euro-American, and Masuko Arai Robinson, who was Japanese. Arai's father fought in World War II; her parents met during the U.S. occupation of Japan and "were committed to healing after World War II". Her biographer, Karma Lekshe Tsomo, states that Arai "learned to code-switch at home, toggling between the language and perspectives of her Japanese mother...and the North American cultural norms and expectations of her Anglo father". Arai's mother did not self-identify as a Buddhist; the family attended her husband's Methodist church services and their children were baptized in the Methodist Church. Arai's mother, however, conveyed her Japanese worldview and Buddhist values to her children and as a result, Arai "internalized her mother's Japanese Buddhist sensibility". Her father valued education, so he supported his daughter's schooling.

Arai earned a bachelor's degree with honors in music and religion from Kalamazoo College in 1983, a Master of Theological Studies from Harvard Divinity School in 1985, a master's degree in the history of religions from Harvard in 1987, a master's degree in Buddhist Studies from Harvard in 1987, and a Ph.D. in comparative religion and Japanese Buddhism also from Harvard in 1993. She studied abroad at Waseda University in Tokyo from 1980 to 1983. While in her Ph.D. program, she was awarded a Fulbright scholarship in support of her dissertation, which included ethnographic and historical research about Japanese Zen nuns. She also received a Edwin O. Reischaeur Institute Grant and a Lilly Foundation Grant that allowed her to study Asian American Christians.

In 1997, Arai served as a translator for Antioch University's Buddhist Studies program, a semester-long undergraduate study abroad program, in Bodh Gaya, India. While in India, she was introduced to the writings of Aoyama Rōshi, the abbess of Aichi Senmon Nisōdō, a monastic training center for Sōtō Zen nuns in Nagoya, Japan. Tsomo called her experience in Bodh Gayā "a pivotal moment in Arai's life". and that it "set into motion a research trajectory that became the centerpiece of her early academic career". Arai was inspired to study the nuns' lives at Aichi Senmon Nisōdō while "embedding herself in the life of the monastery" for four months in the fall of 1989, which became her first book, Women Living Zen: Japanese Soto Buddhist Nuns, published in 1999. Her study was based upon interviews with nuns, surveys of laypeople and nuns, and historical materials, such as publications written for and by nuns. As Suzanne Mrozik states in her review of Women Living Zen in the Journal of Religion, Arai's analysis "centers on the efforts of twentieth-century Soto nuns to create a female monastic tradition that accords with their interpretations of Soto Zen teachings on monasticism and equality".

Arai was influenced by Martin Luther King Jr.; J. Mark Thompson, her professor and a specialist in comparative religion; her mentor John Bunyan Spencer, who introduced her to the philosophy of Alfred North Whitehead; Wilfred Cantwell Smith; James Luther Adams; and Masatoshi Nagatomi, Harvard's first full-time professor of Buddhist Studies. She later reported that the mixed and negatives messages she received during her doctoral education about the validity of a Japanese American woman specializing in the lives and religious practices of Japanese Buddhist women "prepared her to overcome obstacles in order to make the contributions she was poised to make".

When Arai was still a student, she was able to see that women's emotional, spiritual, and intellectual lives were connected, and she wanted to study how, even while pursuing her academic studies. She proposed researching Zen nuns in Japan, but her academic advisors considered it unworthy of study and stalled her dissertation and studies because they did not consider ethnographic studies rational. At Harvard, not only was the topic radical for her time, so was her intention to embed herself into her subjects' lives. The educational establishment resisted Arai's research because they considered it too emotional and Arai experienced professional discrimination as a result, but she pursued her studies and research, anyway. As Tsomo states, "Her vulnerability and honesty about her personal perspective and experience became an asset in her research".