The Bauschinger effect of metals is explored by the multi-scale modeling based on the mathematical homogenization theory without any phenomenological constitutive models such as kinematic hardening. Although this peculiar mechanical behavior was discovered in 19th century, and has been introduced as one of the most typical plastic phenomena for metals in most of basic textbooks for plasticity, the study of this mechanism has been superficial so for. First, we conduct experiments under cyclic loading for specimens with two kinds of microstructures; the pearlite and the spheroidized cementite structures. Then, these experiments exhibiting the Bauschinger effect are simulated by the global-local analysis technique. By focusing our attention to the micro-scale mechanical behavior, we try to explain why and how the effect comes out in experiments.