Inclusion Criteria:  Patients volunteered to participate in this study and signed the informed consent form. Age ≥18, no gender limitation. Patients with malignant solid tumor who have failed or could not tolerate standard treatment and for whom no standard treatment is available.  Recurrent or metastatic solid tumors confirmed by histology; patients who are judged by the investigator to be suitable for treatment with SKLB1028 capsules and who meet the requirements of tumor type for corresponding stages:  Stage I: no restriction on solid tumor types; Phase II: solid tumor type determined by the investigator and the sponsor based on the results of phase I. Stage 1: At least one unmeasurable lesion; Stage 2: At least one measurable lesion according to RECIST v1.1. Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1.  Patient must meet the following criteria as indicated on the clinical laboratory tests:  Absolute neutrophil count ≥1.5×10^9 /L; platelet count ≥80×10^9 /L; hemoglobin ≥90 g/L; Serum creatinine ≤ 1.5 × upper limit of normal (ULN); Total bilirubin ≤ 1.5 × ULN, (≤ 3 × ULN for patients with liver metastasis or liver cancer); Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 3 × ULN (≤ 5 × ULN for patients with liver metastasis or liver cancer). Patient is suitable for oral administration of the study drug. Female patients should agree to use contraceptive measures (such as IUD, condom, etc.) during the study period and within 6 months after the end of the study; negative serum pregnancy test within 7 days prior to enrollment and must be non-lactating patients; male patients should agree to use contraceptive measures during the study period and within 6 months after the end of the study period.  Exclusion Criteria:  The patient have a previous history of severe allergy to drugs and food. Expected survival < 3 months. Other malignant active tumors within the past 3 years; except for cured locally curable cancers, such as basal or squamous cell skin carcinoma, or in situ prostate, cervical or breast cancer. Central nervous system metastasis (excluding brain metastasis with stable symptoms after local treatment) Patients with hepatitis B (HBsAg positive or HBcAb positive with HBV DNA higher than the upper limit of the normal value of the research center) or hepatitis C (HCV antibody positive with HCV RNA higher than the upper limit of the normal value of the research center) or HIV antibody positive. Patients whose toxicity of previous anti-tumor treatment has not recovered to ≤ grade 1. Cardiac dysfunction, including:  QTc interval female ≥ 470 ms, male ≥ 450 ms; Complete left bundle branch block, grade II or III atrioventricular block; Poorly controlled malignant arrhythmias; Cardiac valve regurgitation or stenosis requiring treatment; Cardiac ejection fraction less than 50% within 6 months before screening; Myocardial infarction, unstable angina pectoris, severe pericardial disease, severe myocardial disease occurred within 6 months before screening; History of chronic congestive heart failure with NYHA ≥ grade 3.  Patients have poorly controlled hypertension. Patients have thrombotic or embolic events such as cerebrovascular accident, pulmonary embolism, etc within 6 months before screening. Patients who have received any antitumor treatment within 4 weeks before the first administration; those who have received herbal or proprietary Chinese medicines with a clear antineoplastic indication 2 weeks prior to the first administration. Patients have received other unlisted clinical study drugs within 4 weeks before the first administration.