Ghrelin is a gastric peptide also known as the hunger hormone. It can stimulate the pituitary gland to release growth hormone and is a key peptide that regulates energy metabolism. Ghrelin exists in two forms acylated ghrelin and inactive des-acylated ghrelin. Acylated ghrelin binds to the growth hormone secretagogue receptor GHSR and mediates a variety of physiological functions. In addition to stimulating appetite and increasing food intake ghrelin can also protect heart function prevent muscle atrophy increase bone density regulate stress and anxiety and inhibit inflammatory cytokine production. Ghrelin and its receptors have become potential therapeutic targets for a variety of diseases. In recent years more and more studies have proven that ghrelin and GHSR are abnormally expressed in various tumors and have direct effects on tumor cell proliferation apoptosis autophagy and other functions. They are also closely related to the occurrence and development of tumors through the indirect effects of regulating inflammatory response estrogen production and metabolism. The abnormal expression of ghrelin and its receptor can serve as a marker for diagnosing and predicting the prognosis of various tumors. Additionally drugs targeting ghrelin are gradually being developed and have demonstrated promising efficacy in preclinical studies and clinical trials for both antitumor treatment and supporting therapy for tumor patients. This article will explore the role of ghrelin and its receptors in tumor development their potential as tumor markers and therapeutic targets and review the application of related drugs in tumor patients.