On Whitney-type Characterization of Approximate Differentiability on Metric Measure Spaces We study approximately differentiable functions on metric measure spaces admitting a Cheeger differentiable structure. The main result is a Whitney-type characterization of approximately differentiable functions in this setting. As an application, we prove a Stepanov-type theorem and consider approximate differentiability of Sobolev, $BV$ and maximal functions. Keywords:approximate differentiability, metric space, strong measurable differentiable structure, Whitney theoremCategories:26B05, 28A15, 28A75, 46E35