The authors agree that this surname derives mainly from two related sources: the medieval name Bonaventura, by aphaeresis (loss of the initial syllable), or else directly from the name Ventura, imposed as an omen of good fortune for the newborn. F. Miranda adds, following Ciccia, that the name could also have indicated a foundling, that is, a child of "fortune". P. Canè classifies it among the auspicious surnames, noting that it may respond to an omen, to a novelty or to the abbreviation of Bonaventura or another similar name.

E. Rossoni documents the name Ventura in the Diplomatic Code of medieval Lombardy in the year 1152 in Castelnuovo, as well as in deeds of Portovenere (1259) and Sarzana (1279). He adds that the Venturini of Friuli descend from persons who arrived from Lombardy between 1280 and 1300 in the retinue of the Patriarch of Aquileia Raimondo Della Torre. F. De Laurentiis specifies that the surname reflects the aphaeretic hypocoristic Tura, derived from Ventura, though it may also have been formed directly from ventura, in the positive sense of "favourable luck, fortune".

From the geographical point of view, Miranda notes that the surname is present in more than 1,300 municipalities of all the Italian regions, with concentrations in Lombardy, Emilia-Romagna, Sicily, Apulia, Lazio, Calabria, Piedmont, Veneto, Campania, Liguria and Tuscany. Rossoni specifies the distribution of its variants: Venturi and Venturini are typical of the centre-north of Italy; Venturin is typical of Veneto, with a presence in the Venice, Padua, Treviso and Belluno areas; Venturelli is concentrated in Lombardy, the Verona area and the Modena and Bologna areas; Venturello appears in Piedmont, in the Turin and Asti areas; Venturino is recorded in the Savona and Genoa areas, in Rome, in Campania, in the Crotone area and in the Catania area; Venturoli is typical of the Bologna area and Ferrara; and Venturella corresponds to Sicily, with a presence in Monreale, Palermo, Castelbuono and Campofelice di Roccella.