LCP (Liquid Crystalline Polymer) is widely used for the injection molded parts of small, thin-walled, and fine shapes because of its flowability. In addition superior heat resistance makes injection molded parts possible to use in a hot environment (e.g. reflow furnace for surface mounting using lead-free solder) over 200 degree Celsius. However, strong anisotropy appears in thermal and mechanical properties such as coefficient of thermal expansion and Young’s modulus of the parts for molecular orientation by shearing in a flow-solidification process. Therefore, when using for surface-mounted component under the high temperature environment of the reflow furnace, occurring hot warpage is practical problem and bringing about mold correction. So it is necessary to shorten a mold development lead time using hot warpage simulation in advance. In this report, we covered hot warpage of small LCP thin injection molded part which is difficult to carry out direct TMA measurement for the coefficient of thermal expansion. First, molecular orientation of matrix (LCP) is evaluated by using X-ray diffraction of the small spot. Secondly coefficient of thermal expansion and molecular orientation in same place on an injection molded plate which can be measured by TMA. Thirdly, anisotropy of coefficient of thermal expansion is put into the small part for analysis. Orientation of filler (short glass fiber) is evaluated by using X-ray CT and three-dimensional image processing for fiber extraction. Finally, coefficient of thermal expansion distribution of small part is calculated by homogenization method using matrix and filler orientation data. Hot warpage of part in reflow furnace is computed by finite element analysis using coefficient of thermal expansion distribution and is compared between measured warpage and analyzed warpage. As a result, not only the direction of hot warpage can be predicted but the quantitative amount predictive accuracy is improved.