Blanche Hoschedé Monet was a French painter who was both the stepdaughter and the daughter-in-law of Claude Monet.

Blanche Hoschedé was born in Paris, the second daughter of Ernest Hoschedé and Alice Hoschedé. Ernest was a businessman, a department store magnate in Paris. He collected impressionist paintings and was an important patron to Claude Monet early in his career. In 1876, he commissioned Claude Monet to paint decorative panels in the round drawing room, in his residence, the château de Rottembourg, in Montgeron. In 1877, Ernest Hoschedé went bankrupt and his art collection was auctioned off.

Ernest Hoschedé, Alice, and their six children moved into a house in Vétheuil with Monet, his wife Camille, and their two sons, Jean and the infant Michel. Ernest, however, spent most of his time in Paris, and eventually went to Belgium. After the death of Camille in Vétheuil on 5 September 1879, Alice and her children continued living with Monet. In 1881, they moved to Poissy, and finally settled in their home in Giverny in 1883. Although Ernest and Alice Hoschedé never divorced, Claude Monet and Alice went on living together until after the death of Ernest in 1891. Claude Monet and Alice Hoschedé got married on 16 July 1892.

The only child in the Hoschedé-Monet household to become interested in art, Blanche began painting at the age of eleven and developed a fond relationship with Claude Monet. She visited his studio as well as Édouard Manet's. By the time she was 17 years old, she was Monet's assistant and only student, often painting en plein air alongside him, painting the same subject with the same colors.

Blanche also painted alongside American expatriates Theodore Earl Butler and John Leslie Breck. Monet stopped the romance that had developed between Blanche and Breck, while he allowed Butler to marry Blanche’s sister, Suzanne Hoschedé, in 1892.

The art dealer Paul Durand-Ruel purchased a Haystack painting by Blanche, and it currently is displayed in Monet’s house in Giverny. In January 1888, while in Antibes, Monet encouraged Blanche to submit a work to the Salon.

Blanche married Claude Monet’s eldest son, Jean Monet, in 1897. The couple lived in Rouen, where Jean worked as a chemist for his uncle Léon Monet, and until 1913 in Beaumont-le-Roger.

Her mother, Alice, died on 19 May 1911, and Jean on 10 February 1914, after a long illness. Overcome with grief, Claude Monet suffered from depression and, from that point on, Blanche took over her father-in-law's household. She watched over him as his eyesight was failing him to the point he believed he was going blind. Georges Clemenceau, their common friend, called her Monet's "Blue Angel". After Monet's death on 5 December 1926, and for twenty years until her own in 1947, she took on the responsibility of the house and gardens at Giverny. She died in Nice, aged 82.

Most of Blanche's works were done in Giverny from 1883 to 1897, which was similar to that of Monet's work, and around Rouen. She "adopted an almost pure form of impressionism."

She painted landscapes with trees such as pines and poplars, and meadows along the Risle river. In the 1920s, she also painted on several occasions at Georges Clemenceau's property in Saint-Vincent-sur-Jard (Vendée department) in the west of France - paintings of the garden, house and the Atlantic Ocean. After Monet's death, she remained in Giverny and continued painting. Recognizing her body of work, a street bears her name in the village of Giverny.

Dr. Janine Burke believes that Blanche may have assisted Monet in the painting of the Grandes Décorations. Monet had trained and encouraged Blanche as an artist. In a chapter on Blanche and Monet in Source: Nature's Healing Role in Art and Writing (2009), Burke comments, "Given the sheer scale of the surfaces to be covered in the Grandes Décorations, it is logical to consider Monet had an assistant, and who better than Blanche?"