Background/Aims: Mucosal healing (MH) of distal lesions in ulcerative colitis (UC) has recently been confirmed with budesonide 2-mg foam (BF) treatment in 2 clinical trials; however, few studies have investigated the predictive factors for complete MH. Methods: We conducted a post hoc analysis using pooled data from phase II and III clinical trials evaluating the efficacy and safety of BF for UC. Additionally, we analyzed the relationships between complete MH and baseline factors and clinical symptoms from baseline to week 6. Results: Among the 291 Japanese patients from the 2 pooled clinical studies, 119 patients in the BF twice a day group and 117 in the placebo group were included in the full analysis set. The proportion of patients with a rectal bleeding (RB) subscore of 0 was significantly higher in the BF group than in the placebo group after a 5-day treatment (P<0.05). After a 2-day treatment, significantly more patients in the BF group had a stool frequency (SF) subscore of 0 than patients in the placebo group (P<0.05). Multivariate analysis showed that complete MH at week 6 was influenced by baseline SF subscore and 5-aminosalicylic acid (5-ASA) enema or suppository use (P=0.0086 and P=0.0015, respectively). The relationship between complete MH at week 6 and RB subscore after week 2 was also confirmed. Conclusions Normal SF at baseline, history of 5-ASA topical product use, and elimination of RB after week 2 are suggested predictors of complete MH at week 6 with twice-daily BF treatment.