The first source catalog of Large High Altitude Air Shower Observatory
reported the detection of a very-high-energy gamma ray source, 1LHAASO
J1219+2915. In this paper a further detailed study of the spectral and temporal
behavior of this point-like source have been carried. The best-fit position of
the TeV source (RA=185.05^∘±0.04^∘,
Dec=29.25^∘±0.03^∘) is compatible with NGC 4278 within
∼0.03 degree. Variation analysis shows an indication of the variability at
a few months level in the TeV band, which is consistent with low frequency
observations. Based on these observations, we report the detection of TeV
γ-ray emissions from this low-luminosity AGN NGC 4278. The observations
by LHAASO-WCDA during active period has a significance level of 8.8 σ
with best-fit photon spectral index =2.56±0.14 and a flux
f_1-10 TeV=(7.0±1.1_sta±0.35_syst)×10^-13 photons cm^-2 s^-1,
or approximately 5% of the Crab Nebula. The discovery of VHE from NGC 4278
indicates that the compact, weak radio jet can efficiently accelerate particles
and emit TeV photons.