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<i>Curcuma</i> is extensively cultivated as a medicinal and ornamental plant in tropical and subtropical regions. Due to the bright bract color, distinctive inflorescence and long blooming period, it has become a new favorite in terms of the urban landscape, potted flowers and cut flowers. However, little research on breeding new cultivars using traditional plant breeding methods is available on the genus <i>Curcuma</i>. In the present study, pollen viability and stigma receptivity evaluation were performed, and the genetic relationship of 38 <i>Curcuma</i> accessions was evaluated, then 5 <i>C. alismatifolia</i> Gagnep. (Ca), 2 <i>C. hybrid</i> (Ch), 2 <i>C. sparganiifolia</i> Gagnep. cultivars and 4 <i>Curcuma</i> native species were selected as parents for subsequent interspecific cross-breeding. A total of 132 reciprocal crosses were carried out for interspecific hybridization, including 70 obverse and 62 inverse crosses. Obvious discrepancies among fruit-setting rates were manifested in different combinations and in reciprocal crosses. Results showed that the highest fruit-setting rate (87.5%) was observed in the Ca combinations. There were 87 combinations with a fruit-setting rate of 0%, which meant nearly 65.9% was incompatible. We concluded that <i>C. alismatifolia</i> ‘Siam Shadow’ (Ch34) was suitable as a male parent and <i>C. petiolata</i> Roxb. (Cpet) was suitable as a female parent to improve the fruit-setting rates. The maximum number of seeds per fruit (45.4) was obtained when <i>C. alismatifolia</i> ‘Chiang Mai Pink’ (Ca01) was used as a female parent followed by <i>C. attenuata</i> Wall. ex Baker (Catt) (42.8) and <i>C. alismatifolia</i> ‘Splash’ (Ca63) (39.6) as male parents. The highest germination rate was observed for the Ca group followed by Catt and <i>C. sparganiifolia</i> ‘Maetang Sunrise’ (Csms). The germination rates of Ca accessions ranged from 58.2% (<i>C. alismatifolia</i> ‘Siam Scarlet’ (Ca06) as a male parent) to 89.3% (<i>C. alismatifolia</i> ‘Sitone’ (Ca10) as a male parent) with an average value of 74.0%. Based on the results of hybrid identification, all the individuals from the four combinations exhibited paternal-specific bands, indicating that the true hybrid rates of crossings were 100%. Our results would facilitate the interspecific hybridization and introduction of genetic variation from wild species into the cultivars in <i>Curcuma</i> in the future, which could be helpful in realizing the sustainable application in urban green areas.