  The photometric and spectroscopic investigations of ten contact binaries were
presented for the first time. It is discovered that the mass ratios of all the
ten targets are smaller than 0.15, they are extremely low mass ratio contact
binaries. Seven of them are deep contact binaries, two are medium contact
binaries, while only one is a shallow contact system. Five of them show
O'Connell effect, and a dark spot on one of the two components can lead to a
good fit of the asymmetric light curves. The orbital period studies of the ten
binaries reveal that they all exhibit long-term period changes, six of them are
increasing, while the others are shrinking. The LAMOST spectra were analyzed by
the spectral subtraction method, and all the ten targets exhibit excess
emissions in the H$_\alpha$ line, indicating chromospheric activity. The
evolutionary states of the two components of the ten binaries were studied, and
it is found that their evolutionary states are identical to those of the other
contact binaries. Based on the study of the relation between orbital angular
momentum and total mass, we discovered the ten systems may be at the late
evolutionary stage of a contact binary. The initial masses of the two
components and the ages of them were obtained. By calculating the instability
parameters, we found that the ten contact binaries are relatively stable at
present.
