  Three-nucleon short-range correlation ($3N$ SRC) represents a rare and
intriguing part of the nuclear dynamics at short distance, beyond the
two-nucleon short-range correlation ($2N$ SRC). To search its existence is a
hot topic in the ongoing and future high-energy nuclear experiments and the
developments of nuclear theory. In this study, we found a positive sign of $3N$
SRC in nuclei, by analyzing the correlation between the per-nucleon nuclear
mass and the probability of a nucleon in $2N$ SRC state, with the current
experimental measurements of $^2$H, $^3$He, $^4$He, $^9$Be, $^{12}$C,
$^{27}$Al, $^{56}$Fe, Cu, $^{197}$Au and $^{208}$Pb from SLAC, CLAS, and JLab
Hall C collaborations. The effective masses of the nucleons in $2N$ SRC and
$3N$ SRC are also extracted from the analysis, which provide some references
for the nuclear medium effect study. The probability of $3N$ SRC is much
smaller than that of $2N$ SRC, thus requiring high-luminosity experiments to
confirm its existence.
