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Abstract The purpose of this work is to develop a single-phase phosphor emitting white light under the excitation of near UV light, targeted at the possible application in white light emitting diodes. Our rationale is to employ a host containing noncentrosymmetric coordination sites for rare earth, therefore the f - f absorptions in the near UV range could be enhanced. Indeed, YGa 3 (BO 3) 4 is such a host where Y3+ is in a twisted triangular prism and could be substituted by various rare earth elements. The photoluminescence of Dy3+ and Tm3+ were investigated in Y 1- x Dy x Ga 3 (BO 3) 4 (0 ≤ x ≤ 0.10) and Y 1- y Tm y Ga 3 (BO 3) 4 (0.01 ≤ y ≤ 0.10), whose phase purity was confirmed by powder X-ray diffraction. Dy3+ emits yellowish white light and Tm3+ emits blue light under their respective f - f excitations (350 and 358 nm). The optimal concentrations in the singly-doped phosphors are 7 and 3 atom%, respectively. When co-doping Dy3+ and Tm3+ in YGa 3 (BO 3) 4 , there was no energy transfer between them. Eventually, a white light emission could be obtained with the CIE coordinates of (0.325, 0.329) in Y 0.91 Dy 0.07 Tm 0.02 Ga 3 (BO 3) 4 under the excitation of 364 nm. Graphical abstract Dy3+ and Tm3+ singly and co-doped YGa 3 (BO 3) 4 were synthesized by solid state reactions. Rietveld refinements confirmed that Dy3+ and Tm3+ replace Y3+ and locate in a triangular prism environment, which is beneficial for their f - f absorptions in near UV range. Since there is no energy transfer, tuning the content of Dy3+ and Tm3+ leads to the white emission with the CIE coordinate of (0.325, 0.329). fx1 Highlights • Structural refinements confirmed Dy3+/Tm3+ locates at the Y3+ site in YGa 3 (BO 3) 4. • Dy3+ and Tm3+ emit yellowish white and blue light in YGa 3 (BO 3) 4 , respectively. • The optimal concentration for Dy3+ is 7 atom% in Y 1- x Dy x Ga 3 (BO 3) 4. • The optimal concentration for Tm3+ is 3 atom% in Y 1- y Tm y Ga 3 (BO 3) 4. • Near UV excited white emission can be obtained in Y 0.91 Dy 0.07 Tm 0.02 Ga 3 (BO 3) 4. [ABSTRACT FROM AUTHOR]