Lamprophyllite group minerals are the general name of titanosilicate minerals rich in Sr, Na, Ca and Ba etc. So far, there are 19 mineral species, of which fluorlamprophyllite was found in the alkaline rocks of the Serrote Mountain in Brazi for the first time. In this paper, the mineralogical characteristics of the lamprophyllite group minerals in the Saima alkaline rock pluton in Liaoning Province, China, have been studied in detail in terms of chemical composition and crystal structure by means of electron probe micro-analysis and X-ray diffraction. The results show that the minerals occur mainly in columnar, acicular and fibrous aggregates, and the single crystals are in sheet and plate shape. The crystal chemical formula is (Sr_1.00Na_1.00)_Σ2.00Ti₂(Na_1.98Sr_0.33Mn_0.26K_0.12Mg_0.10Ca_0.09Ba_0.05)_Σ2.93(Ti_0.69Fe³⁺_0.33Al_0.02)_Σ1.04(Si_3.80O₁₄) O₂(F_1.16OH_0.84)_Σ2.00. It belongs to monoclinic system, with the space group of C2/m. The unit-cell parameters are a=19.271 9(8) Å, b=7.077 9(3) Å, c=5.388 2(2) Å, β=96.780(2)°, V=729.84(5) ų, Z=2. The mineralogical characteristics mentioned above are consistent with those of fluorlamprophyllite which is a new mineral discovered in the alkaline rock of the Serrote Mountain in Brazil for the first time, and the fluorlamprophyllite studied in this paper is the first discovered in China. At the same time, it is pointed out that the Saima alkaline pluton also includes lamprophyllite, and it implies that there is still a good prospect for the discovery of new minerals in the pluton because of its special element combination and formation conditions.