To date, few studies have focused on protostellar outflow feedback at scales larger than several parsecs. To address this paucity of research, we investigate the effects of feedback from CO outflow candidates on their parent clouds over ~110deg^2^ toward the W3/4/5 complex and its surroundings. Our search identified 265 ^13^CO clouds with radii being ~0.04-17.12pc. We estimate the turbulent support and potential disruptive effect of the outflow activities through analyzing physical properties of outflow candidates and their host clouds in terms of turbulence and gravitational binding energy. We find that (1) clouds of larger size might be less affected by feedback; (2) the possible scale break is >~4.7pc for both turbulent support and potential disruptive effect; (3) if outflows couple to dense gas where stars are forming, for clouds in the Perseus arm, a scale <~0.2-0.4pc is sufficient for the energy and momentum injected by outflow activity to maintain turbulence, while for clouds in the Local arm, the scale is <~0.1-0.2pc; and (4) for clouds in the Perseus arm, a scale <~0.3-1.0pc is needed for outflow activity to potentially disperse material away from the natal clouds, while for clouds in the Local arm, the scale is <~0.2-0.6pc. The strength of outflow activity may affect the values in points 3 and 4. Finally, we find that outflow feedback probably possesses the power to alter the line width-size relation.