A dual-wavelength 1.0 μm Q-switched and 1.5 μm gain-switched pulsed fiber laser is demonstrated by using a single Er/Yb co-doped gain fiber. Experimental setup consists of two loop resonators with one common branch including the Er/Yb co-doped fiber. The 1.0 μm Q-switched pulses are generated via the saturable absorption effect of the unpumped Er/Yb co-doped fiber, whereas a reabsorption of 1.0 μm Q-switched pulses from the Yb ions modulates the population inversion of Er ions periodically to generate 1.5 μm gain-switched pulses at the same repetition rate of 1.0 μm Q-switched pulses. With the increasing of pump power, the repetition rates of both pulses vary from 5.4 kHz to 11.7 kHz. However, the 1.5 μm pulses have a delay relative to 1.0 μm pulses, and the delay decreases with the increasing of pump power. At the maximum pump power, the pulse duration, single pulse energy and average output power for 1.0 μm pulses are 5.3 μs, 402.6 nJ and 4.7 mW respectively, whereas they are 4.6 μs, 374.4 nJ and 4.4 mW respectively for 1.5 μm pulses.