Curcuma zanthorrhiza Roxb. produces significant quantity of curcumin and essential oil in its rhizomes, hence can be used as an alternate source of curcumin. The differential expression of curcumin synthase (CURS) genes and subsequent curcumin production varied at the different developmental stages of the plant. The present study focused on the relative quantification of putative CURS (CURS1, CURS2 and CURS3) genes using qRT-PCR from the rhizomes of C. zanthorrhiza in comparison with C. longa L. and ultra fast liquid chromatography assisted curcumin quantification in both the species. The curcumin content in the rhizomes of C. zanthorrhiza were 111.6 µg/g, 352.6 µg/g, 776.2 µg/g and in C. longa were 72.5 µg/g, 140.1 µg/g and 1705.7 µg/g at the 3rd, 6th and 9th month growth stages respectively. The relative expression of putative CURS1 was 2.39 ± 0.03–6.54 ± 0.06 fold, CURS2 was 1.74 ± 0.01–3.24 ± 0.18 fold and CURS3 was 1.61 ± 0.23–3.48 ± 0.13 fold in C. zanthorrhiza and 3.58 ± 0.13–10.4 6 ± 0.11 fold for CURS1, 1.51 ± 0.06–4.92 ± 0.10 fold for CURS2 and 1.80 ± 0.03–7.01 ± 0.14 fold for CURS3 in C. longa, during the 3rd–9th month with the highest relative expression in the six-month old rhizomes of C. zanthorrhiza and C. longa. The CURS expression was positively correlated with the curcumin content in both the species during the 3rd and 6th month, however, during the 9th month the curcumin content increased and the putative CURS gene was down-regulated. The levels of expression of CURS genes are in the order with the highest expression for the CURS1, followed by CURS3 and CURS2. Thus, it can be suggested that C. zanthorrhiza can be pertinently supersede as an alternate for C. longa.