Triangular-lattice cobaltates with glaserite-type $X_{2}Y\mathrm{Co}{\left(T{\mathrm{O}}_4\right)}_2$ structure provide an ideal platform to investigate intriguing quantum magnetism. Here we report a comprehensive study of the structural and magnetic properties of a triangular-lattice cobalt vanadate ${\mathrm{Na}}_2\mathrm{SrCo}{\left({\mathrm{VO}}_4\right)}_2$. Room-temperature x-ray and neutron powder diffraction confirm that ${\mathrm{Na}}_2\mathrm{SrCo}{\left({\mathrm{VO}}_4\right)}_2$ crystallizes in the monoclinic $P{2}_1/c$ space group with slightly distorted triangular layers of ${\mathrm{Co}}^{2+}$ ions. Magnetization measurements reveal a ferromagnetic transition at $T_{\mathrm{C}}\approx 3.4\mathrm{K}$, where a sharp $\lambda$-type anomaly is observed in the specific heat. The magnetic entropy recovered up to 55 K approaches $90\%$ of $R\ln 2$, supporting an effective spin-1/2 state of ${\mathrm{Co}}^{2+}$ ions at low temperature. Neutron diffraction at 2.3 K (below $T_{\mathrm{C}}$) further confirms a long-range canted ferromagnetic order with the ${\mathrm{Co}}^{2+}$ moments aligned in the $ac$ plane and the ordered moment size of $\sim$ 2.6 ${\mu }_{\mathrm{B}}$. Comparing with its sister compounds with a trigonal symmetry, ${\mathrm{Na}}_2\mathrm{BaCo}{\left({\mathrm{VO}}_4\right)}_2$ with a collinear ferromagnetic structure and the recently discovered spin supersolid candidate ${\mathrm{Na}}_2\mathrm{BaCo}{\left({\mathrm{PO}}_4\right)}_2$ with a distinct Y-like antiferromagnetic ground state, this study indicates the decisive role of the $T{\mathrm{O}}_4$ tetrahedra in tuning exchange interactions and contrasting magnetic behaviors of these glaserite-structure compounds.

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• Magnetic order
• Triangular lattice
• Magnetization measurements
• Neutron diffraction