In this paper, fixed point theorems using ψ contractive mapping in ${\mathrm{C}}^{\ast }$-algebra valued b-metric space are introduced. By stating multiple scenarios that illustrate the application domains, we demonstrate several applications from the obtained results. In particular, we begin with the definition of the positive function and then recall some properties of the function that lay the fundamental basis for the research. We then study some fixed point theorems in the ${\mathrm{C}}^{\ast }$-algebra valued b-metric space using a positive function.