QCD ASPECTS OF LEPTOQUARK PRODUCTION AT HERA Christer Friberg Emanuel Norrbin Torbj\"orn Sj\"ostrand If a leptoquark is produced at HERA as a narrow resonance, various effects tend to broaden the measurable mass distribution considerably. These effects are discussed here, with special emphasis on initial- and final-state QCD radiation. A proper understanding is important to assess the significance of data and to devise strategies for better mass reconstruction. LU TP 97-05, April 1997 Phys.Lett. B