The present invention addresses a need to construct a synthetic-resin spinning reel spool for limiting production of sink marks on the outer surface thereof. A spinning reel spool 4 is attached onto a spool shaft 16 mounted movably back and forth in a reel unit 1 for winding a fishing line thereon. The spool 4 includes a front flange 4c, a rear flange 4b and a bobbin trunk 4a. The rear flange 4b is disposed rearwards of the front flange 4c. The bobbin trunk 4a includes a plurality of coupling ribs 25 circumferentially disposed at predetermined intervals for coupling the front and rear flanges 4c and 4b. The bobbin trunk 4a is integrally formed with the front and rear flanges 4c and 4b, while having a diameter less than diameters of the front and rear flanges 4c and 4b.對於紡車式捲線器的合成樹脂製的捲筒,可抑制捲筒的外側面中的縮痕的發生。紡車式捲線器的捲筒(4),是被裝設於可朝前後移動地設在紡車式捲線器的捲線器本體(1)的捲筒軸(16)供捲附釣線用。捲筒(4),具有:前凸緣部(4c)、及後凸緣部(4b)、及捲線胴部(4a)。後凸緣部(4b),是被配置於前凸緣部(4c)的後方。捲線胴部(4a),是具有使前凸緣部(4c)及後凸緣部(4b)連結的方式在周方向隔有間隔地被配置的複數條連結部(25),且比前凸緣部(4c)及後凸緣部(4b)小徑地與兩者一體形成。4...捲筒4a...捲線胴部4b...後凸緣部4c...前凸緣部4d...裙部4e...釣線卡止部4f...第2薄壁部4g...第1薄壁部4h...凹陷部25...連結部26...連結筒部27...前壁部28a...貫通孔54...捲筒調整鈕55...止轉構件55a...外周面56...出聲構件57...捲筒承接
