It is a new attempt to investigate thermal stability and reactivity of four 3-Phenyl-2-propene compounds by MCPVT. The temperature of initial oxygen absorption (Ta) and rapid oxidation(TR) were calculated. Results showed that four 3-Phenyl-2-propene compounds were stable under nitrogen atmosphere. The Ta of cinnamaldehyde, cinnamyl alcohol, β-methylstyrene and cinnamic acid were 271.25K, 292.375K, 323.125K, and 363.875K, and the TR of cinnamaldehyde, cinnamyl alcohol, β-methylstyrene and cinnamic acid were 301.125K, 332.75K, 357.91K, and 385.375K, respectively. The oxidation reactivity order was derived: cinnamaldehyde > cinnamyl alcohol > β-Methylstyrene > cinnamic acid. The oxidation kinetics of four 3-Phenyl-2-propene compounds was calculated, which showed a second-order reaction. Peroxide concentrations of initial oxidation were determined by iodimetry, and the oxidation products were analyzed by gas chromatography-mass spectrometry (GC-MS). Results showed peroxides were generated. According to the complex oxidation products, important insights into the pathways of oxidation were provided.