This is a first-in-human, non-randomized, open-label, multi-center, phase I study in patients with advanced solid tumor to evaluate the safety and tolerability, PK, immunogenicity, and preliminary anti-tumour activity of T320. This study consists of a dose escalation module and a backfill module. The trial process for each subject in both escalation and backfill module includes a screening period (28 days before the first T320 administration), a treatment period (from the first T320 administration to the end of reatment), a safety follow-up period (28 days after EOT/early withdrawal) and a progression follow-up period (every 12 weeks from safety follow-up visit). Patients will receive T320 administration once every 2 weeks (Q2W) and 28 days are set as one treatment cycle.