Paper presents results of the effect of removing the first flush primocanes on vegetative growth, yield and fruit quality of blackberry cultivar ‘Čačanska Bestrna’. Primocanes were removed on a single (10 of May) or double (10 of May and 1 of June) occasions. Removing the first flush primocanes had impact on number of fruiting branches developed in current year on floricanes, but no on their length. It was observed that treatments with removing primocanes had significantly higher yield per bush and per unit area. Increasing of yields was ranged from 11.4% (removal of primocanes twice) to 15.1% (removal of primocanes once). Fruit weight and soluble solids content in the blackberry fruits were not significantly different under the influence of various term of the removal of the first flush of primocanes. The aforementioned pomotechnical measure has significantly influenced the properties of newly developed blackberry primocanes.U radu su prikazani rezultati uticaja uklanjanja prvih serija izdanaka na vegetativni rast, prinos i kvalitet ploda kupine sorte ‘Čačanska bestrna’. Izdanci su uklanjani u jedan (10. maja) ili dva navrata (10. maja i 1. juna). Uklanjanje je uticalo na broj rodnih grančica razvijenih u tekućoj godini na dvogodišnjem izdanku kupine, ali ne i na njihovu dužinu. Prinos po žbunu i jedinici površine je bio značajno veći u varijantama uklanjanja prvih serija izdanaka nego kada oni nisu uklanjani. Povećanje prinosa se kretalo od 11,4% (uklanjanje izdanaka dva puta) pa do 15,1% (uklanjanje izdanaka jednom). Masa ploda i sadržaj rastvorljive suve materije u plodovima se nisu značajno razlikovali pod uticajem različitih varijanti uklanjanja prvih serija izdanaka kod kupine. Uklanjanje prvih serija izdanaka u toku vegetacije je značajno uticalo na osobine novorazvijenih izdanaka kupine