Due to drug resistance, the clinical response to cisplatin (CDDP) from patients with liver cancer is unsatisfactory. The alleviation or overcoming of CDDP resistance is an urgent problem to be solved in clinics. Tumor cells rapidly change signal pathways to mediate drug resistance under drug exposure. Here, multiple phosphor-kinase assays were performed and c-Jun N-terminal kinase (JNK) was activated in liver cancer cells treated with CDDP. The high activity of the JNK promotes poor progression and mediates cisplatin resistance in liver cancer, leading to a poor prognosis of liver cancer. Mechanistically, the highly activated JNK phosphorylated c-Jun and ATF2 formed a heterodimer to upregulate the expression of Galectin-1, leading to promoting cisplatin resistance in liver cancer. Importantly, we simulated the clinical evolution of drug resistance in liver cancer by continuous CDDP administrationin vivo.In vivobioluminescence imaging showed the activity of JNK gradually increased during this process. Moreover, the inhibition of JNK activity by small molecular or genetic inhibitors enhanced DNA damage and overcame CDDP resistancein vitroandin vivo.Collectively, our results underline that the high activity of JNK/c-Jun-ATF2/Galectin-1 mediates cisplatin resistance in liver cancer and provides an optional scheme for dynamic monitoring of molecular activityin vivo.