Achillini graduated from Bologna in 1484 with his doctorate in both medicine and philosophy. He immediately began his advancement through the academic ranks by teaching philosophy and, after 1495, he also taught medicine. He left Bologna for Padua in 1506 because of political difficulties and returned in 1508 to teach until his death four years later.
During his lifetime he was most highly regarded as a teacher of logic and philosophy, and little attention was paid to his medical or anatomical contributions. His Opera omnia was first published in 1508. The contents of the book include: De intelligentiis, De orbibus, De universalibus, De physico auditu, De elementis, De subiecto physionomiae & chiromantiae, De subiecto medicinae, De prima potestate syllogismi, De distinctionibus and, De proportione motuum.
His works were generally on the thought and doctrine of Aristotle. In the latter tract Achillini asserts that physiognomy and chiromancy are speculative sciences and not wholly practical. It was his belief that they were subordinated to natural philosophy.