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In this paper, we investigate Cesàro means for the weighted orthogonal polynomial expansions on spheres with weights being invariant under a general finite reflection group on <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mi mathvariant="double-struck">R</mi><mi>d</mi></msup></semantics></math></inline-formula>. Our theorems extend previous results only for specific reflection groups. Precisely, we consider the weight function <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>h</mi><mi>κ</mi></msub><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>:</mo><mo>=</mo><msub><mo>∏</mo><mrow><mi>ν</mi><mo>∈</mo><mi>R</mi><mo>+</mo></mrow></msub><msup><mrow><mo>|</mo><mfenced separators="" open="⟨" close="⟩"><mi>x</mi><mo>,</mo><mi>ν</mi></mfenced><mo>|</mo></mrow><msub><mi>κ</mi><mi>ν</mi></msub></msup><mo>,</mo><mspace width="4pt"></mspace><mi>x</mi><mo>∈</mo><msup><mi mathvariant="double-struck">R</mi><mi>d</mi></msup></mrow></semantics></math></inline-formula> on the unit sphere; the upper estimates of the Cesàro kernels and Cesàro means are obtained and used to prove the convergence of the Cesàro <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>(</mo><mi>C</mi><mo>,</mo><mi>δ</mi><mo>)</mo></mrow></semantics></math></inline-formula> means in the weighted <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mi>L</mi><mi>p</mi></msup></semantics></math></inline-formula> space for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>δ</mi></semantics></math></inline-formula> above the corresponding index. We also establish similar results for the corresponding estimates on the unit ball and the simplex.