The female flowers or cones of the common hop plant (Humulus lupulus) are important sources of alpha and beta acids, terpenes and flavonoids that are used as flavouring and aroma agents in beer making. These specialised metabolites are synthesized and stored in the glandular trichomes or lupulin glands located on female flowers. Hops are a global crop and Australia is the 5th largest exporter of hops in the world, boasting of hop varieties with flavours unique from varieties grown in other countries. In this study, we investigated changes in proteome and phosphoproteome during female flower development in the flavour hop variety Cascade. Cascade flowers impart distinct characters such as floral aroma and grapefruit flavour to finished beer. Flowers were collected at eight different stages of development (from one-week old flowers to mature flowers). Changes in the proteome and phosphoproteome were correlated to three distinct periods namely early, mid and late stages of flower development using label-free quantitative proteomics. We identified various proteins involved in flower maturation and production of terpenes, bitter acids and secondary metabolites that contribute towards the unique flavour and aroma of this cultivar. Based on the phosphoproteome data, we report proteins involved in regulation and accumulation of specialised metabolites providing insights into biological processes that occur during flower maturation. The comprehensive data generated through this study will contribute to our understanding of hop flower development at a molecular level with potential applications in plant breeding programs.