In Marthe au chapeau blanc, Pierre Bonnard presents a striking portrait of a woman, likely his muse, Marthe. The painting is characterized by vibrant colors, particularly the soft whites and warm tones that create a lively atmosphere. The white hat stands out prominently, drawing the viewer's attention to her face and expression.

Bonnard's use of light and shadow adds depth, making the figure appear almost three-dimensional. The painting is executed in oil on canvas, a medium that allows for rich texture and color blending. Bonnard's brushwork is loose yet intentional, contributing to the overall impressionistic feel of the piece. The dimensions are approximately 65 x 54 cm, making it a medium-sized portrait that invites close viewing.

The composition focuses on the subject, with minimal background distractions enhancing her presence. Pierre Bonnard was a key figure in the Post-Impressionist movement, known for his innovative use of color and light. Marthe au chapeau blanc reflects his deep affection for his partner, Marthe, who often served as his model. This work is notable for its intimate portrayal, capturing not just her likeness but also a sense of her personality.

Interestingly, Bonnard often painted from memory, which adds a layer of spontaneity to his works.