Disclosed by the present invention are a compound represented by formula (I) and an anti-tumor application thereof. The compound represented by formula (I) has a degrading and inhibiting effect on an anaplastic lymphoma kinase (ALK)-targeted protein, and is mainly composed of four parts: the first part, i.e., ALK-tyrosine kinase inhibitors (TKIs), is a compound having the activity of inhibiting an ALK tyrosine kinase; the second part, i.e., LIN, is a different linker; the third part, i.e., a ubiquitin ligase binding moiety (ULM), is a small molecule ligand of VHL, CRBN or other proteases having a ubiquitination function; and the fourth part, i.e., group A, is a carbonyl group or a default, which covalently binds the ALK-TKIs and the LIN, the LIN covalently binding to the ULM. The series of compounds designed and synthesized in the present invention have wide pharmacological activities, have the functions of degrading ALK proteins and inhibiting ALK activity, and may be used for related tumor treatment.