Portrait of Maria Portinari is a small c. 1470–72 painting by Hans Memling in tempera and oil on oak panel. It portrays Maria Maddalena Baroncelli, about whom very little is known. She is about 14 years old, and depicted shortly before her wedding to the Italian banker, Tommaso Portinari. Maria is dressed in the height of late fifteenth-century fashion, with a long black hennin with a transparent veil and an elaborate jewel-studded necklace. Her headdress is similar and a necklace identical to those in her depiction in Hugo van der Goes's later Portinari Altarpiece (c. 1475), a painting that may have been partly based on Memling's portrait.

The panel is the right wing of a devotional and hinged triptych; the lost center panel is recorded in sixteenth-century inventories as a Virgin and Child, and the left panel depicts Tommaso. The panels were commissioned by Tommaso, a member of a prominent Florentine family. Tommaso was a confidant of Charles the Bold and an ambitious manager of the Bruges branch of a bank controlled by Lorenzo de' Medici, and a well known and active patron of Flemish art. Tommaso eventually lost his position due to a series of large and risky unsecured loans given to Charles.

Maria and Tommaso's portraits hang alongside each other at the Metropolitan Museum of Art in New York. The central panel is lost; some art historians suggest it may have been his Virgin and Child in the National Gallery, London.

The portrait was commissioned by the art-loving Tommaso as the right-hand wing of a triptych. She was placed opposite her husband, with a now-lost central Madonna and Child. Their small size and intimacy suggest that the portraits were commissioned for private prayer; some art historians believe, given Tommaso's cultural acumen and preoccupation with his social standing, that they were partially accessible to the public. The triptych may have been intended for the Portinari Chapel, located behind the apse of the Basilica of Sant'Eustorgio, Milan, and constructed between 1462 and 1468.

Maria would have been around 14 years old at the time the portrait was commissioned, either the year of her marriage in 1470 or shortly after. Tommaso represented the Medici bank in Bruges, but after a promising early career he gave a number of risky and unsecured loans to Charles the Bold which were left unpaid and eventually led to the branch's insolvency. He died young, and when the portrait was first mentioned as part of his collection in 1501, he was no longer alive. Maria is recorded as being alive at the time; she was executor to her husband's will but her fate thereafter is uncertain. The 1501 inventory places both portraits as wings, with a central Virgin and Child panel; "a small, valuable panel painting, with an image of Our Lady in the middle and on the sides painted Tommaso and mona Maria his wife" (una tavoletta dipinta preg[i]ata cum nel mezo una immagine di Nostra Donna e delle bande si è Tommaso e mona Maria sua donna dipinti in deta tavoletta).

The half-length portrait shows Maria Portinari (born Maria Maddalena Baroncelli in 1456) in a three-quarter view turned to the left. She has somewhat Nordic features, and is dressed in the high fashion then found at the apex of Flemish and Italian high society. She is placed against a flat, opaque, dark background, with her hands clasped in prayer. In Memling's early portraits the backgrounds tend to be plain, as was invariably the case in the work of Jan van Eyck and Rogier van der Weyden, and favored within Burgundian court circles. In contrast, Memling's later portraits are set within rich interiors or against landscapes framed by columns, such as in his Portrait of Benedetto Portinari [it], a fact that has assisted in dating his work.

Maria's face is idealised and conforms to contemporary ideals of beauty, especially in the raised eyebrows and elongated nose. The art historian Lorne Campbell has noted her facial similarity to the Virgin in Memling's panel at the National Museum of Ancient Art, Lisbon. In this work, Maria's frame is slightly undersized compared to her head, a common characteristic of contemporary northern portraiture, also found in similar works by Rogier van der Weyden and Petrus Christus. Her elbows rest on an unseen parapet that coincides with the lower edge of the painted stone frame, acting as a trompe-l'œil which situates her both in the same reality and in closer proximity to the viewer. Maria wears a relatively modest wedding band lined with rubies and sapphire. Her necklace is colored with mostly red and blue jewels, similar to Hugo van der Goes's portrait of her in the Portinari Altarpiece.

The black hennin is long, truncated and relatively plain with a transparent veil which falls around the back of her neck, resting briefly on her shoulder. Probably it was kept relatively unadorned so as not to distract from the necklace. Her costume is mostly black or brown, with a wide but high neckline and white fur lined hems on the sleeves. Portinari has dark eyes, a strong nose, full lips and a pointed chin. Her visible hand, folded in prayer but unrealistically off center, wears what looks like a jeweled ring. The dark sleeves of her dress contain red or rouge velvet-like cloth tightened by a white belt. Her hair is shaved back to achieve the high forehead and sculptural look fashionable at the time.