The facile one-step assembly reaction of Na2WO4 center dot 2H(2)O, Sn(CH3)(2)Cl-2, RE(NO3)(3)center dot 6H(2)O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-alpha-TeW7O28} and {W5O18} mixed building units [H2N-(CH3)(2)](8)Na4H2[RE2(OH)(B-alpha-TeW7O28)Sn-2(CH3)(4)(W5O18)](2)center dot 18H(2)O [RE = Er-III (1), Yb-III (2) Ho-III (3), Y-III (4)]. The most striking structural characteristic of 1-4 is that they all contain a novel tetrameric S-shaped RE2(OH)(B-alpha-TeW7O28)Sn-2(CH3)(4)(W5O18)](2)(14-) moiety simultaneously including two pentavacant Keggin [B-alpha-TeW7O28](12-) and two monovacant Lindqvist [W5O18](6-) fragments connected by RE and dimethyltin linkers. To the best of our knowledge, such dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from Er-III and Ho-III centers. Moreover, various 1-Er/Yb co-doped samples were prepared by controlling different mass ratio of Er(NO3)(3 center dot)6H(2)O/Yb(NO3)center dot 6H(2)O in the range of 0.96:0.04-0.02:0.98. In the visible region, the emission intensity of the 1-Er-0.40/Yb-0.60 co-doped sample reaches the maximum at the mass ratio of Er(NO3)(3)center dot 6H(2)O/Yb(NO3)center dot 6H(2)O being 0.40:0.60, and this observation is mainly derived from the fact that the Yb3+ ions can sensitize the Er3+ ions to enhance the emission intensity in the visible region. However, no such phenomenon for the 1-Er/Yb co-doped samples is seen in the NIR region. Besides, the upconversion spectra of the 1-Er/Yb co-doped samples were first observed. In addition, the thermal stabilities of 1-4 were also investigated on the crystalline samples and the thermal decomposition process of 1 has been deeply studied.