The Portinari Chapel (Italian: Cappella Portinari) is a Renaissance chapel at the Basilica of Sant'Eustorgio, Milan, northern Italy. Commenced in 1460 and completed in 1468, it was commissioned by Pigello Portinari as a private sepulchre and to house a silver shrine given by Archbishop Giovanni Visconti in 1340 containing the relic head of St. Peter of Verona, to whom the chapel is consecrated. The architect is unknown, the traditional attribution to Michelozzo having been succeeded with equal uncertainty by attributions to either Filarete or Guiniforte Solari, architect of the apses of the Certosa di Pavia and the church of San Pietro in Gessate in Milan.

The Portinari Chapel, which has been described as a work of Tuscan architecture in Lombardy, was commissioned by the Florentine nobleman Pigello Portinari (1421–1468), who became the representative in Milan of the Medici bank in 1452. (His younger brother Tommaso, also a Medici banker and patron, would commission the Portinari altarpiece from Hugo van der Goes in 1475.) The building was intended to function both as a family chapel and mortuary and to house the relics of Saint Peter of Verona who, as patron saint of inquisitors, was of particular importance to the Dominicans of Sant’Eustorgio: their convent had housed the Milan inquisition since the 1230s.