The interaction between CO2 laser and polyformaldehyde(POM)is quite important in the research of laser irradiation effects and mechanisms.At this time,the accuracy of the existing mass-ablation models for POM irradiated by CO2 laser is poor compared with the experimental data.Based on the energy distribution deposited in the POM target,the active area excited by laser is divided into four slices,the ablation slice(the temperature-rising slice,the perturbation slice,and the undisturbed slice),and a slicing response model for the mass ablation of POM induced by pulsed CO2 laser irradiation in vacuum is developed.A formula is deduced to predict the ablated mass areal density from the model and is verified with data from several studies and our own experiments.The results show that our model fits the experimental data quite well before the shielding effect of ablation products becomes notable.The applicability of the model to other materials and the mass ablation in atmosphere are also briefly explored. The interaction between CO2 laser and polyformaldehyde (POM) is quite important in the research of laser irradiation effects and mechanisms. At this time, the accuracy of the existing mass-ablation models for POM irradiated by CO2 laser is poor compared with the experimental data. Based on the energy distribution deposited in the POM target, the active area excited by laser is divided into four slices, the ablation slice (the temperature-rising slice, the perturbation slice, and the undisturbed slice), and a slicing response model for the mass ablation of POM induced by pulsed CO2 laser irradiation in vacuum is developed. A formula is deduced to predict the ablated mass areal density from the model and is verified with data from several studies and our own experiments. Results show that our model fits the experimental data quite well before the shielding effect of ablation products becomes notable. applicability of the model to other materials and the mass ablation in atmosphere are also bri efly explored.