He always acknowledged that his early style had been influenced by study of a Madonna painted by Ludovico Carracci for the Capuchin church in Cento, affectionately known as "La Carraccina".

[11] The dramatic composition of this canvas (related to his Flaying of Marsyas by Apollo (1617–1618[12]) created for The Grand Duke of Tuscany, which shares the same pair of shepherds[13]) is typical of Guercino's early works, which are often tumultuous in conception.

[14] He painted two large canvases, Samson Seized by Philistines (1619) and Elijah Fed by Ravens (1620), for Cardinal Serra, a Papal Legate to Ferrara.

In 1655, the Franciscan Order of Reggio paid him 300 ducats for the altarpiece of Saint Luke Displaying a Painting of the Madonna and Child (now in Nelson-Atkins Museum of Art, Kansas City).

Guercino's drawings are known for their fluent style in which "rapid, calligraphic pen strokes combined with dots, dashes, and parallel hatching lines describe the forms".

[24] challenges the more measured representation of the same subject painted by Guido Reni at Palazzo Rospigliosi on behalf of a Ludovisi family rival and makes a statement of political triumph.

A groundbreaking exhibition held at the Archiginnasio of Bologna in 1968 provided the most complete panorama of Guercino's work to date, including paintings from the later parts of his career after the death of Pope Gregory XV, which had previously attracted relatively little attention.

[39] For the fourth centenary of the artist's birth in 1991, an expanded exhibition was organized by the Pinacoteca Nazionale di Bologna in conjunction with the Schirn Kunsthalle Frankfurt and the National Gallery of Art, Washington.