The development and progression of colorectal cancer (CRC) are highly dependent on the long-term inflammatory microenvironment with immune dysregulation in the colorectum. However, effective therapeutics are limited to targeting CRC. Here, we developed oral fullerene tablets (OFTs) that can act directly on the colorectal site by oral administration and reduce the inflammatory state at the tumor site for effective CRC therapy. In detail, OFTs scavenged reactive oxygen species (ROS), restrained the mutation of the wild-type P53, inhibited the activation of the inflammatory pathway nuclear factor-κB (NF-κB) and the signal transducer and activator of transcription 3 (STAT3) in the colorectum of CRC mice. Subsequently, OFTs could greatly reduce the infiltration of pro-inflammatory M1 macrophages and neutrophils at the tumor site, restoring the inflammatory microenvironment and immune homeostasis in the colorectal region, and ultimately achieving the inhibition of CRC. In addition, there were no significant toxic side effects of the long-term administration of OFTs. Our work provides an effective oral therapeutic strategy for CRC therapy by modulating the colorectal tumor inflammatory microenvironment and sheds light on the route for oral nano-materials in the clinical treatment of CRC.