In order to explore the genetic law of cucumbers fruit spine base size，this paper took 2 cucumber inbred lines CNS5 with large fruit spine base and RNS4 with small fruit spine base as parents to construct 6 generations：P1，F1，P2，B1，B2 and F2；and utilized the major gene + polygene mixed inheritance model to
analyze the phenotypic values of cucumber fruit spine base size．The results indicated that inheritance of cucumber fruit spine base size conforms to C-0 model，namely additivity-dominance-epistasis polygene model．Multi-gene additive，dominant and epistatic effects were all positive．Additionally，the polygene inheritabilities in F2 from 2016 and 2017 were 79.21% and 71.25%，respectively，which was relatively higher．The environmental effects in F2 was 20.79% and 28.75%，respectively，which had relatively smaller influence．Therefore，this study has provided a foundation for exploring genes related to fruit spine base size．As strategy for gene mapping，selecting high generation backcross populations will have better effect．