Acidification of tumor microenvironment is associated with aggressive tumor growth and facilitate resistance to anti-cancer therapies. Extracellular pH (pHe) mapping with BIRDS is used to differentiate ablated and non-ablated tumors in the setting of systemic immunotherapy of murine colorectal cancer. Combination of Cryoablation with Dual Immune Checkpoint Blockade (DICB) resulted in a significant pHe increase compared to control tumors. This work demonstrates the feasibility of measuring pHe with BIRDS in a murine colorectal cancer model. pHe imaging could serve as a non-invasive imaging biomarker for tumor microenvironment assessment and monitoring of metabolic changes after immuno-thermal ablation therapy.