The raw experimental data set for the manuscript "Mechanical compression in cofacial porphyrin cyclophane pincers" published in Chemical Science. It includes the raw data for the experimental results in Figure 2 and 3 of the manuscript. The goal of the research is to measure the intramolecular transport properties of a porphyrin double decker in a single-molecule junction via the MCBJ technique. The data are collected with the MCBJ conductance measurements, as functions of electrode displacement and time.