The 1991 Individual Speedway Junior World Championship was the 15th edition of the World motorcycle speedway Under-21 Championships.

Brian Andersen won the final, defeating fellow Dane Morten Andersen in a run-off for the title after both riders had finished on 14 points.

Qualifying

Semi-finals

World final

PlacingRiderTotal1234567891011121314151617181920PtsPos21
Denmark (10) Brian Andersen14323331413
Denmark (14) Morten Andersen14233331422
Australia (9) Jason Lyons1112233113
4Australia (15) Shane Parker103331E104
5England (1) Joe Screen10F3322105
6Denmark (7) Jacob Olsen93220296
7Sweden (13) Niklas Klingberg80113387
8Denmark (16) Frede Schött81222188
9Sweden (4) Joakim Karlsson623F0169
10Soviet Union (6) Viktor Gajdym620121610
11Sweden (12) Jimmy Engman621012611
12Poland (2) Piotr Paluch531100512
13Poland (3) Robert Kużdżał411110413
14Poland (5) Marek Hućko3102E0314
15Hungary (8) Zsolt Böszermenyi2F0011215
16Poland (11) Adam Łabędzki00X---016
R1Poland (R1) Jacek Rempała2022R1
R2England (R2) Dean Barker222R2
PlacingRiderTotal1234567891011121314151617181920PtsPos21

m - exclusion for exceeding two minute time allowance • t - exclusion for touching the tapes • x - other exclusion • e - retired or mechanical failure • f - fell • ns - non-starter • nc - non-classify

gate A - insidegate Bgate Cgate D - outside