In Vietnam and China the leaves of Urceola rosea are widely used as herbal remedy and food. However, in contrast to the plants stem, little information was available on major constituents. In this study, the first in-depth phytochemical investigation of U. rosea leaves is described, which resulted in the isolation of thirteen compounds, mainly flavonoids (kaempferol and quercetin derivatives) and triterpenes. Furthermore, an analytical procedure for the quantification of five major compounds was developed. The HPLC separation was performed on a Synergi MAX-RP column using acetonitrile and 0.1% formic acid as mobile phase. Method validation confirmed that the assay shows good linearity (R2 ≥ 0.9997), precision (intra-day R.S.D ≤ 4.31%, inter-day R.S.D ≤ 3.52%) and accuracy (recovery rates ranged from 96.8 to 102.6%). Detection limits were always lower than 0.07 μg/mL. The analysis of several plant samples revealed distinct differences, as for example the content of total phenolics varied from 0.44 to 1.73%.