(1) Background: The present study aims to evaluate the reduction of postoperative pain in breast surgery using a series of local analgesics, which were infiltrated into the wound; (2) Methods: Envelopes containing allocation were prepared prior to the study. The patients involved were randomly assigned to the groups of local anesthesia infiltration (Group A) or normal pain management with intravenous analgesics (Group B). The random allocation sequence was generated using computer-generated random numbers. The normally distributed continuous data were expressed as the means (SD) and were assessed using the analysis of variance (ANOVA), independent-sample t-test, or paired t-test; (3) Results: The development of the postoperative pain stages was recorded using the VAS score. Therefore, for Group A, the following results were obtained: the VAS at 6 h postoperatively showed an average value of 0.63 and a maximum value of 3. The results for Group B were the following: the VAS score at 6 h postoperatively showed an average value of 4.92, a maximum of 8, and a minimum of 2; (4) Conclusions: We can confirm that there are favorable statistical indicators regarding the postoperative pain management process during the first 24–38 h after a surgical intervention for breast cancer using local infiltration of anesthetics.