Previous studies have investigated the executive control process of deceptive behavior. There is a relative lack of electrophysiological mechanism of spontaneous deception of adolescents from the perspective of decision-making processing. Combined with event-related potential (ERPs), this study used dots task and timely feedback paradigm to explore the intrinsic mechanism of adolescents' spontaneous deception. In this study, 34 college students were selected as paid volunteers, of which 2 were due to artifacts seriously, processing data were excluded, finally got 32 effective participants (14 girls, average age 20.22 ±1.58). In this experiment, the dots task was used to control the level of spontaneous deception of the participates, and timely feedback paradigm was used to manipulate the outcome evaluation of the participates. In the experimental task, 20 black spots were randomly arranged in the left and right boxes of the computer screen(13: 7, 14: 6 , 15: 5), and the corresponding integral values (10, 20, 100) were presented. It is possible that the participants will get a corresponding integral value when they choose a box. The computer will give feedback on the outcome after each choice, including failed deception, successful deception and honesty. The participates were told that they could only withdraw from the experiment if they had accumulated 10,000 integral values. Meanwhile, participants' EEGs were recorded by a 64-channel ERPs equipment while they were taking the experimental task. In the decision-making process, the resulting amplitudes of P300 were entered into 2 elicited conditions (high reward, low reward) × 2 reactions (honesty, deception) ANOVAs for repeated measures. In the outcome evaluation process, FRN amplitude were entered into 2 elicited conditions (high reward, low reward) × 3 feedback types ( failed deception, successful deception, honesty) ANOVAs for repeated measures. ERPs analysis revealed that the main effect of deceptive reaction type was significant, (F (126) = 10.73, p <0.01, η2 ≤0.29), that is, deceptive decision-making elicited more higher amplitude of P300 than honest decision-making (Mdeceptive＝2.79±0.49μV; Mhonest＝1.67±0.55μV). The main effect of outcome evaluation type was significant, (F (250) = 10.63, p < 0.01, η2≤0.30), compared with successful deception feedback and honest feedback, failed deception feedback elicited more negative FRN (p＜0.01). There was no significant difference in FRN elicited by successful deception feedback and honest feedback(Msuccessful deception＝-3.08±0.75μV; Mfailed deception＝-6.69±1.09μV; Mhonest＝-3.06±0.75μV). These results revealed that individuals who make deceptive decision require more attention resource and mental efforts than honest decisions. Compared with successful deception feedback and honest feedback, they are more sensitive to failed deception feedback. It’s not only help to better understand the dynamic mechanism of adolescents spontaneous deception, but also lays a research foundation for educators to take necessary measures to reduce and prevent the deceptive behavior of adolescents.