We studied the prognostic value of in colorectal cancer (CRC) using bioinformatics. exhibited differential expression between the tumor and control samples, and improved survival was observed in patients with increased expression. The univariate and multivariate analyses confirmed as an independent prognostic factor for CRC, based on which a nomogram was constructed for predicting survival in patients with CRC. Additionally, higher expression was correlated with increased immunological/stromal/ESTIMATE scores as well as immune cell infiltration and was strongly and positively associated with T helper cells and macrophages. Furthermore, significant positive correlations were observed between SIGLEC1 expression and inhibitory/coinhibitory immunological genes. Additionally, the TIDE results of patients with CRC showed that increased expression was related to poorer immunotherapeutic responses. In clinical samples from patients with CRC, a decrease in expression was noted compared to para-cancerous tissues and samples from patients who received Yiqi Huayu Jiedu Decoction (YHJD) treatment. The results indicated the superior efficacy of YHJD against CRC in inhibiting tumor metastasis. Our study demonstrates that SIGLEC1 serves as a prognostic factor for CRC, strongly linked to immune response, and can be modulated by YHJD, suggesting novel avenues for CRC treatment.