A multivoltine silkworm breed can produce quality silk seed with considerable resistance to diseases. The study isolated and characterized multivoltine breeds at the Sericulture Research and Development Institute in Northern Philippines, and evaluated their performance on four quantitative characters such as single shell weight (SSW), single cocoon weight (SCW), cocoon shell percentage (CSP) and cocoon yield per box CYB -1 ) in three rearing seasons (January-February, August-September and October-November). Locally acquired silkworm hybrid cocoons were processed and isolated following the Mass Selection Method. The study was laid out in Randomized Complete Block Design with 3 replications. Data gathered were subjected to Analysis of Variance (ANOVA) and further tested using Least Significant Difference (LSD). Three multivoltine breeds were isolated and characterized DMMMSU 1002, DMMMSU 1003 and DMMMSU 1016.In January-February season, DMMMSU 1002 performed better than the check breed, DMMMSU 1000 in all the economic parameters tested, but only on SSW in August-September; SCW and CYB -1 in October-November seasons. DMMMSU 1003 performed better than DMMMSU 1000 in all the parameters evaluated in January-February; for SSW in August-September); and SCW in October-November rearing seasons.DMMMSU 1016 performed better on SSW and CSP (January-February); CYB -1 (August-September) and SSW, SCW and CSP in October-November rearing season. Based on these findings, the newly isolated lines can be used as potential parents of superior silkworm hybrids for higher cocoon yield.