Objective To explore the efficacy of bevacizumab in combination with FOLFOX standard chemotherapy for the treatment of postoperative patients with oligometastatic colorectal cancer and its impact on the median progression-free survival （mPFS）. Methods The clinical data of postoperative patients with oligometastatic colorectal cancer admitted to Fuyang People's Hospital from January 2021 to June 2024 were retrospectively collected. Based on the treatment regimens received after surgery， the patients were divided into the combination group （bevacizumab + FOLFOX standard chemotherapy， n = 30） and the chemotherapy group （FOLFOX standard chemotherapy， n = 72）. All patients completed 6 cycles of treatment （with 21 days as 1 cycle）. The therapeutic effects， serum marker levels before and after treatment ［carcinoembryonic antigen （CEA）， carbohydrate antigen 199 （CA199）， platelet count/lymphocyte count ratio （PLR）， lymphocyte count/monocyte count ratio （LMR）， C-reactive protein/albumin ratio （CRP/ALB）］， and toxic and side effects of the two groups were systematically counted， analyzed， and compared. The follow-up survival outcomes were compared （with follow-up conducted once every 3 months until November 1， 2025）. Additionally， the correlation between serum markers and the survival prognosis of patients was analyzed， and Cox regression analysis was employed to screen the prognostic factors of patients. Results The overall efficacy grade of the combined group was superior to that of the chemotherapy group， and the disease control rate （DCR） was higher （P < 0.05）. After treatment， the levels of serum CEA， CA199， PLR， and CRP/ALB in the combined group were lower than those before treatment within the same group and those after treatment in the chemotherapy group （P < 0.05）， whereas the LMR was higher （P < 0.05）. There was no statistically significant difference in the incidence of toxic and side effects between the two groups （P > 0.05）. At the end of the follow-up， the combined group exhibited longer average progression-free survival （PFS）， median PFS （mPFS）， average overall survival （OS）， and median OS （P < 0.05）. A total of 102 patients were classified into the progression group （progression or tumor-related death， n = 62） and the non-progression group （surviving during follow-up， n = 40） based on survival prognosis. At the end of treatment， the levels of serum CEA， CA199， PLR， and CRP/ALB in the progression group were higher than those in the non-progression group， while the LMR was lower （P < 0.05）. At the end of treatment for patients with oligometastatic colorectal cancer， serum CEA， CA199， PLR， and CRP/ALB were negatively correlated with mPFS and median OS， whereas LMR was positively correlated with mPFS and median OS （P < 0.05）. Cox regression analysis indicated that high CEA and high CRP/ALB were independent risk factors for the prognosis of patients with oligometastatic colorectal cancer （P < 0.05）， while bevacizumab + FOLFOX chemotherapy and high LMR level were protective factors （P < 0.05）. Conclusions Bevacizumab combined with FOLFOX standard chemotherapy can enhance the disease control rate among postoperative patients with oligometastatic colorectal cancer， decrease the expression level of tumor-related factors， and offer a better survival prognosis with controllable adverse reactions when compared with chemotherapy alone.