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We examine an inflationary model in $R + R^2$ gravity with torsion, where$R^2$ denotes five independent quadratic curvature invariants; it turns outthat only two free parameters remain in this model. We show that the behaviorof the scale factor $a(t)$ is determined by two scalar fields, axial torsion$\chi(t)$ and the totally anti-symmetric curvature $E(t)$, which satisfy twofirst-order differential equations. Considering $\dot{\chi}\approx 0$ duringinflation leads to a power-law inflation: $a \sim (t+ A)^p$ where $1< p \leq 2$, and the constant $A$ is determined by the initial values of $E$, $\chi$ andthe two parameters. After the end of inflation, $\chi$ and $E$ will enter intoan oscillatory phase.

Inflation in $R + R^2$ Gravity with Torsion