Background and Objective: COVID-19 pandemic led to major disruptions in surgical activity in 2020, with the exception of oncological and urgent procedures. Then, starting from 2021 there was a progressive return to routine. The Italian National Surgical Site Infection Surveillance (SNICh) continued. Therefore, the aim of this study was to assess the impact of the pandemic on abdominal surgery outcomes in Piedmont, a region in northern Italy. Methods: Data on abdominal surgery, divided into oncological and non-oncological procedures, were collected from 42 hospitals participating in the regional surveillance network from 2018 to 2021. Predicted surgical site infection (SSI) rates for 2020 and 2021 were estimated on pre-pandemic (2018-2019) data and compared with the observed rates, using Mantel-Haenzel corrected chi-squared tests. The expected SSI rates were predicted on the basis of pre-pandemic data stratified by Infection Risk Index (IRI). To avoid competing risk bias, patients deceased within the 30-day follow-up period were excluded. Analyses were performed using Epi Info V7.2. Results: In the pre-pandemic period 5268 procedures and 307 SSIs were recorded. In 2020 there were 1031 interventions and 44 SSIs, while in 2021 there were 1490 interventions and 112 SSIs. In 2020, the observed SSI rate for oncological procedures (6.07) was significantly lower (p<0.001) than the expected (7.33). However, in 2021 the observed SSI rate for non-oncological procedures (7.86) was significantly higher (p=0.03) than the expected (5.13). The other results did not reach statistical significance. Conclusions: The lower SSI rate for oncological procedures during the pandemic (2020) may highlight an increased attention to infection prevention and control practices. On the other hand, it seems that the delay in the interventions affected the risk of SSI after the pandemic peak (2021), but only for procedures that have actually been delayed such as non-oncological ones.