As FinFET scaling down to sub-14 nm technology nodes, fin profile and Critical Dimension (CD) control is becoming a huge challenge due to increased number of processes. For a stable wafer-to-wafer CD performance, Advanced Process Control (APC) system is widely deployed in high volume manufacturing production. In this work, we present a novel implementation of APC-based fuzzy control system in fin etching process within the widely-used Self-aligned Quadruple Patterning (SaQP) scheme. Feed-forward APC are applied to the two processes: 1) Atomic Layer Deposition (ALD) process for fin hard-mask etching and 2) fin etching process with a fuzzy control. With the deployment of the APC system, the inline metrology variation performance of fin CD improved from ±3.5% to ±1.8%. The Cp and Cpk are increased by 18% for various key inline parameters. The APC-based fuzzy control scheme shows a great potential for the sub-14 nm nodes.