We present the results based on the optical $R$-band polarization observations of 280 stars distributed towards the dark globule LDN,1225. {it Gaia} data release 2 parallaxes along with the polarization data of $sim$200 stars have been used to (a) constrain the distance of LDN,1225 as 830$pm$83~pc, (b) determine the contribution of interstellar polarization (ISP), and (c) characterize the dust properties and delineate the magnetic field (B-field) morphology of LDN,1225. We find that B-fields are more organized and exhibit a small dispersion of 12$degr$. Using the $^{12}$CO molecular line data from the Purple Mountain Observatory (PMO), along with the column density, dispersion in B-fields, we estimate B-field strength to be $sim$56,$pm$,10,$mu$G, magnetic to turbulence pressure to be $sim$3,$pm$,2, and the mass-to-magnetic flux ratio (in units of critical value) to be~$<$,1. These results indicate the dominant role of B-fields in comparison to turbulence and gravity in rendering the cloud support. B-fields are aligned parallel to the low-density parts (traced by $^{12}$CO map) of the cloud, in contrast they are neither parallel nor perpendicular to the high-density core structures (traced by $^{13}$CO and C$^{18}$O maps). LDN,1225 hosts two 70,$mu$m sources which seem to be of low-mass Class 0 sources. The total-to-selective extinction derived using optical and near-infrared photometric data is found to be anomalous ($R_{V}$~$=$~3.4), suggesting dust grain growth in LDN,1225. Polarization efficiency of dust grains follows a power-law index of $-$0.7 inferring that optical polarimetry traces B-fields in the outer parts of the cloud.
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