Thanks for the bug report! Storing the icon size seems to work for me in 4.2.0 (Kubuntu) and trunk rev. 919065. But note that the issue has been reported again in bug 182550, so it seems that it really does not work for some users. Strange.

I've tried to manually set IconSize in ~/.kde/share/apps/konqueror/profiles/webbrowsing
But konqueror overwrote IconSize value to 22.

To me, this also looks like a duplicate of #175085:
https://bugs.kde.org/show_bug.cgi?id=175085

@Hannes: This is no duplicate of bug 175085, toolbar icons are stored in a different way than the icon size of the view mentioned in bug 175085.

Hi, there is kde 4.2.85 , but this bug haven't been resolved, is it normal?
It is very annoying bug! 
Please, fix it at least in 4.3!

*** Bug 194831 has been marked as a duplicate of this bug. ***

(In reply to comment #5)
> Please, fix it at least in 4.3!

I'm still unable to reproduce the bug using the steps you described (trunk rev. 975689), everything works as expected here. Could you try to create a new user and see if the new user also has this problem? Maybe you have some broken settings stored in your configuration files.

May be it's important, widget style is oxigen.

I can reproduce this problem with new clean user.
I've created new user 
login 
start konqueror, change icon size to small -> save settings in profile -> close/start -> main toolbar icons againg default( 22x22 )size, but location toolbar is 16x16.
ok, I again change icon size to small, save,logout/login, start konqueror. Nothing change:( icon size is default == medium, again

I'm also using Oxygen. I tried again with a fresh KDE configuration on 4.2.3 (Kubuntu) and trunk, opened Konqueror, right-clicked on the Main Toolbar, set the Icon size to 16x16, closed and reopened Konqueror -> Icon size is remembered correctly, even if I don't save it in the profile.

I'm using fedora 10, may be this is the important difference...
What did you set in konqueror settings -> perfomance -> preloading -> maximum number of instances kept preloaded: 1 
?

I'm also using Fedora 10 with KDE 4.2.2. The problem *cannot* be reproduced here.
As, explained in comment #9, right-clicking on the main toolbar and chaning icon size works. I didn't even save the view profile.

@Nikita: Are you sure you are right-clicking the main toolbar? It seems the main toolbar and the location toolbar have their own size settings. i.e. you can change the icon size of one without affecting the other.

Yes, I'm sure that I've tried main toolbar and location toolbar
I've tried lock toolbar position and save, also. Icons size aren't remembered:(
More over I've tried change IconSize value to 16 in file: $HOME/.kde/share/apps/konqueror/profiles/webbrowsing
[Profile]
FullScreen=false
Height 1024=986
Name[$e]=Web Browsing
RootItem=Tabs0
State=AAAA/wAAAAD9AAAAAAAABQAAAAOkAAAABAAAAAQAAAAIAAAACPwAAAACAAAAAgAAAAMAAAAWAG0AYQBpAG4AVABvAG8AbABCAGEAcgEAAAAAAAABKAAAAAAAAAAAAAAAGABlAHgAdAByAGEAVABvAG8AbABCAGEAcgAAAAAA/////wAAAAAAAAAAAAAAHgBsAG8AYwBhAHQAaQBvAG4AVABvAG8AbABCAGEAcgEAAAEoAAABtgAAAAAAAAAAAAAAAgAAAAMAAAAeAGIAbwBvAGsAbQBhAHIAawBUAG8AbwBsAEIAYQByAAAAAAD/////AAAAAAAAAAAAAAAWAGgAdABtAGwAVABvAG8AbABCAGEAcgAAAAAA/////wAAAAAAAAAAAAAAHgByAGUAbABsAGkAbgBrAHMAVABvAG8AbABCAGEAcgAAAAAA/////wAAAAAAAAAA
Tabs0_Children=ViewT0
Tabs0_activeChildIndex=0
ViewT0_LinkedView=false
ViewT0_LockedLocation=false
ViewT0_PassiveMode=false
ViewT0_ServiceName=khtml
ViewT0_ServiceType=text/html
ViewT0_ToggleView=false
Width 1280=1280
XMLUIFile=konqueror.rc

[Profile][Toolbar bookmarkToolBar]
Hidden=true
Index=3
ToolButtonStyle=TextBesideIcon

[Profile][Toolbar extraToolBar]
IconSize=22
Index=1
ToolButtonStyle=TextUnderIcon

[Profile][Toolbar htmlToolBar]
IconSize=22
Index=4
ToolButtonStyle=IconOnly

[Profile][Toolbar locationToolBar]
IconSize=22
Index=2
ToolButtonStyle=IconOnly

[Profile][Toolbar mainToolBar]
IconSize=22
Index=0

[Profile][Toolbar rellinksToolBar]
IconSize=22
Index=5
ToolButtonStyle=TextBesideIcon


After that, I started konqueror and toolbar icon size where small, but after restarting konqueror first time this file were changed(all lines with IconSize where removed), and iconsize in toolbar was medium(22x22)
I restarted konqueror again and this file have changed again - lines with IconSize=22 where added

Hi, what else can I do to change status of this bug?

(In reply to comment #13)
> Hi, what else can I do to change status of this bug?

Well the only way the status of the bug will change is when someone is able to reproduce the problem. Since no one has been able to do that, the status remained the same.  Anyhow, I cannot reproduce this either in the latest KDE v4.7.4 release ; so fell free to reopen the ticket if you still have this problem in the same or newer release of KDE.