  Low-energy scattering processes of vector meson and nucleon are an important
window for studying non-perturbative QCD. The interaction of vector meson with
nucleon, vector meson-nucleon scattering length $|\alpha_{VN}|$, is an
important component of the study of hadronic interactions. Nowadays many
scattering length values $|\alpha_{VN}|$ have been reported using the recent
photoproduction experiment data or quasi data. In addition, the study of trace
anomalous energy contribution to the proton mass is also a hot topic in
non-perturbative QCD and hadron physics. However, it is difficult to measure
proton trace anomalous energy experimentally, and the study of the trace
anomaly of proton is still inconclusive. In this study, we established the
relationship between the scattering length of the vector meson-proton
$|\alpha_{Vp}|$ and the trace anomaly contribution of the proton mass $T_{A}$.
With the scattering length values extracted by using the Vector Meson Dominance
model, we obtained the trace anomaly contribution of the proton mass $T_{A}$ =
(22.8$\%$ $\pm$ 1.2$\%$), which is of similar order of magnitude as the 23$\%$
given by Lattice QCD calculation. We conjecture that the trace anomaly
contribution of nucleon is independent of the type of vector meson probe. We
hope that high precision measurements of vector meson-nucleon scattering length
could give us a better chance to explore the origin of the nucleon mass.
