The relation between star formation rates (SFRs) and magnetic field is still a mystery. Through a comparison between the surveys of SFRs and a study of cloud–field alignment—which revealed a bimodal (parallel or perpendicular) alignment—we show that the perpendicular alignment tends to have lower SFRs per solar mass. This indicates that B-fields are a primary regulator of SFRs: a perpendicular cloud-field alignment has higher magnetic flux than parallel cases and the support of the gas against self- gravity is stronger. Moreover, cloud fragmentation and magnetic field alignment is found to be selfsimilar (e.g. Li et al. 2015). Whether the bimodal SFR is also selfsimilar can only be answered with a higher resolution of magnetic- field detection. I will also introduce APol, the ASTE Polarimeter, which I am leading to build for this purpose.