A modular fly fishing rod system includes elongated rod blanks configured for mutual end-to-end removable engagement, with adjacent rod blanks having mutually distinct transverse cross-sections to form a rod portion extending from a proximal end having a relatively large transverse cross-section, to a distal end having a relatively small transverse cross-section. The rod blanks include intermediate rod blanks and a tip top rod blank, in which each intermediate rod blank has one or more helical line guides configured to permit the fishing line to be moved transversely into and out of engagement therewith. A handle has a reel seat to support a fishing reel, and a chuck configured to releasably engage any of the rod blanks, wherein the handle may be selectively used with the tip top rod blank alone or with one or more of the intermediate rod blanks engaged therebetween to selectively vary the length of the rod portion.