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Blue and orange-emitting, KNa_3−xSi₄Al₄O₁₆:xCe³⁺ and KNa_3−ySi₄Al₄O₁₆:yYb²⁺ were synthesized through solid-state reaction. Analyses of structural properties of the phosphors were performed through Rietveld refinement of the XRD pattern, and the luminescence properties were analyzed by activation with Ce³⁺ and Yb²⁺ ions. On excitation with 397 nm source, photoluminescence (PL) spectra Ce³⁺ activated compound was found to be a typical blue asymmetric emission band originating from 5d¹ → 4f¹(²F_7/2 and ²F_5/2) transitions of Ce³⁺ ions. On exciting with 442 nm source, Yb²⁺ activated samples showed an orange broad emission band, due to transitions in the 4f¹³5d¹ and 4f¹⁴ levels. The temperature dependence of PL was analyzed for both phosphors, and Yb²⁺ doped compound showed a rapid thermal quenching of luminescence, compared to Ce³⁺ doped compound, as is expected for higher stokes shift emission bands.