Inclusion Criteria:  Male or female subjects greater than or equal to 18 years old； Written informed consent obtained prior to any study-related procedure being performed; Subjects with life expectancy ≥3 months; Eastern Cooperative Oncology Group performance score 0 - 2; Subjects must have histologically or cytologically confirmed advanced or metastatic solid tumor; At least one measurable lesion based on RECIST version 1.1 .  Exclusion Criteria:  History of other malignancies within 3 years before screening,unless radical non-melanoma skin cancer or basal cell carcinoma of the skin or carcinoma in the situ of the cervix; Have central nervous system metastases; Prior treatment with SHP2 inhibitor; Have major surgery within 28 days prior to the first dose of GH21; Left ventricular ejection fraction (LVEF) <50 %; Females who are pregnant or breastfeeding ; Active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection; Conditions that the investigator considers inappropriate for participation in this clinical trial.