He was born in Lucca, the son of the city's lord Paolo Guinigi and his second wife Ilaria del Carretto. He started on a military career early in his life and in 1425 he was hired by the Republic of Florence at the head of 700 knights, and later by Filippo Maria Visconti, lord of Milan. He left in 1428, returning to Lucca, which was at the time under pressure from Florence. He fought alongside Francesco Sforza, but was captured and detained at Milan for an unknown period, after which he lived in exile.
The last mention of Ladislao is in a plot (1443–1444) with Spinetta Fregoso, lord of Sarzana, to restore the family lordship in his home city, but the plan was discovered and thwarted. The date of his death is unknown.
