This paper highlights the major findings on the genetic studies of Hevea leaf disease (Colletotrichum, Corynespora and Oidium) resistance using 18 selected genotypes and progenies from a five-parent diallel cross population. Results of the investigations showed that Colletotrichum and Corynespora resistance had moderate heritability estimates while Oidium resistance had relatively lower values. General combining ability (GCA) effects were important in controlling all the three disease resistance traits. Specific combining ability (SCA) effects were demonstrated to be important in accounting for the variation of Corynespora and Oidium resistance. Reciprocal effects were not detected for these diseases; and the relative magnitude of GCA to SCA was 37 (range: 25.6-40.0) for Colletotrichum; 4.6 (range: 1.4-11.1) for Corynespora and 2.0 (range: 0.5-4.8) for Oidium resistance.