The kinetics of topographic changes of the polypropylene (PP) surface modified in non-equilibrium plasma of the DC discharge in oxygen and its flowing afterglow has been studied. For afterglow the distance between discharge zone and sample end was 0.06 m. The linear flow rate was the constant. The sample temperature was regulated by external thermostat and it was 333 K. The pressure of plasma-forming gas was 100 Pa, discharge current was 80 mA. The treatment time was change in the range of 10-60 minutes. The surface structure was observed by AFM method (microscope “Solver 47 Pro”). As a rule roughness of film material is described via a value of root mean square deviation in surface unevenness dimensions (RMS). In addition we used following characteristics: maximal and middle unevenness height (depth) – Amax and Amid respectively and their relationship Amid/Amax also. The experiments showed the following. The action of both oxygen plasma and its afterglow results in the formation pores in PP surface. Presence of pores can be found out visually on sample microphotographs (45 μm *45 μm) and also by changes of values RMS, Amax, Amid and Amid/Amax. There is some induction period (~ 1 minute), when pores can not be found out visually and characteristics remain those values that for untreated PP. Dispersion in diameter and depth of pores can be considerable. For example diameter of pores on the same microphotograph varies from ~0.3 μm (ability limit of visual detection of pore) to 15 μm for plasma and from ~0.3 μm to 8 μm for afterglow at some conditions. It is evidence of significant space heterogeneousness of polymer (density variations, presence of crystal and amorphous strips and etc.). Magnitude’s variations of topographic characteristics - RMS, Amax and Amid –are in 2-3 times as much for the plasma action as compared with flowing afterglow during the same period of time. Nature of kinetic changes of values RMS, Amax, Amid and Amid/Amax and also visual observations allow to assume the following. Processes of surface modification have been occurred in thin surface layer (less 100 nm) if period of treatment time is all of one minute. Stages of oxidative destruction initiation of polymer materials were investigated and described previously [1]. It is period when the active centers are formed on surface. They are sites of evolution of future pores. In state conditions PP etching goes on by deepening and broadening of pores. When treatment time is increased maximal depth of pores grows nonlinearly reaching 2 μm in plasma and 1 μm in afterglow and not changes later. At 10 minutes of activation magnitude of value Amid/Amax passes through maximum. Apparently initially process etching-out of pores begins from “weak places” relatively quickly. One is retarded in 10 minutes and is stopped after a while (30-40 minutes in plasma and 20 minutes in afterglow). Simultaneously in this process more “hard places” are involved where the same takes place. Thus regularities of topographic changes on PP surface modified in plasma of discharge in oxygen and its flowing afterglow are qualitatively similar, differences are quantitative. In conditions of afterglow action on polymer of ultraviolet quantum’s and charged particles is eliminated and also proportion of flows of atoms and excited molecules is changed considerably as compared with plasma. Calculation of relative reduction in concentrations of O(3P), O2(a1Δg) and O2(b1Σg -) reached sample in afterglow gives magnitudes 0.74, 0.82 and 0.01 respectively [2]. According to finding in state conditions of oxygen plasma activation a depth of change of PP surface relief is substantially greater then thickness of oxidizing layer. The last is not exceed 10 nm as usual there is assumed.